Nikon Camera and Lens Information and Repair

Preface

Author and Copyright

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DISCLAIMER

If there is no electronic flash, the greatest risk is torn flesh from sharp sheet metal or gear teeth. ;-)

We will not be responsible for damage to equipment, your ego, county wide power outages, spontaneously generated mini (or larger) black holes, planetary disruptions, or personal injury or worse that may result from the use of this material.

Introduction

Recommended Tools

• Screwdrivers: Most of the fasteners in modern cameras and lenses are very small Philips/Star head screws. Older equipment will tend to have flat head screws. Some are smaller than a quarter grain of normal rice - not the long grain variety. ;-). High quality screwdrivers are essential for both. Otherwise there is the real risk of chewing up the heads making it impossible to ever remove or replace them. Magnetized blades are desirable to hold the screws while they are installed as most are ferrous. The Dollar Store jeweler's screw driver sets are NOT generally satisfactory. The fit and quality may be mediocre. I use a Husky™ combination Philips/flat blade set.

  For the specific case of the (mostly older) flat head screws, fabricating a driver with an aluminum blade is recommended to prevent damage to the screw slots. These screws also tend to have long thin slots, which don't fit the typical screwdriver well at all. The special tool can be as simple as an aluminum roofing nail with its point filed down to a thin blade. Damage to the screw slots is almost unavoidable with a steel screwdriver, and at the very least, looks bad. ;( The softer blade will get chewed up after a while but that can be repaired.

  Most in modern Nikon cameras and lenses are self-tapping plastic screws with a coarse thread. For the few metal parts, they are fine-thread machine screws. There are several sizes used and they are not interchangeable! So it's best to keep track of the specific screws at each step by storing them in plastic baggies. Pill organizers are also useful but an accidental whack can send the screws all over the place. ;-(

  NEVER use excessive torque in tightening screws! It doesn't take much to strip threads in soft plastic, especially for the tiniest screws. And take care not to start the screw at an angle and cross-thread the hole. There will be definite resistance but should never be an indication of bottoming. That probably means the wrong screw length was used. If it seems more difficult to install than to remove, it's probably the wrong screw.

  A very few screws in cameras have a left-hand thread. I've seen exactly one (1) case of this - in the Copal Square S shutter (used in the Nikkormat FT/FTN among others) - which secures the "Slow Speed Lever" or "Retard Drive Cam" depending on which manual is being referenced. But be on the lookout - if the screw seems to get tighter, try the other way. ;-) Being overzealous and breaking or stripping the screw shaft would likely be fatal to the camera both because finding a replacement screw would be impossible and the remains of the screw is solidly stuck in the hole. ;-(

• Soldering equipment: There may be some solder connections that need to be disconnected and then reconnected, or simply repaired. Newer cameras and lenses tend to have more of these but even a 40+ year old film camera may have a few. A low power soldering iron, thin rosin-core solder and a desoldering tool are essential.

• Magnifier: An eye loupe and/or magnifying eye glasses will be essential - along with a bright light. Eye loupes are inexpensive and magnifying eye glasses can be made using a pair of reading glasses and an eye loupe glued to one of its lenses. There are also pricey telescopic glasses available. A stereo zoom microscope may come in handy but is probably not essential. The bright light is. ;-)

• Work area: All disassembly/reassembly should be done on a surface that is soft like cloth or paper with a raised lip or rim surrounding it. These will minimize the chance of tiny parts bouncing away into oblivion. A bio-hazard glove box may be even better. I once spent over an hour searching for the aforementioned left hand shutter screw because I neglected to adhere to my own recommendataions. ;( ;-)

Service and Repair Manuals for Nikon Gear

• Manuals at non-Nikon Websites: The largest collections of on-line repair and parts manuals for Nikon equipment appears to be at Learn Camera Repair. The Website can be searched which will probably be quickest to locate a specific manual. Most or all of the downloads were free until recently (2025). Now the typical manual is under $4. And there is now an eBay user (321 Go Rabbit Pro Gear) who seems to be reselling the same manual PDFs for $11.99 - a greater than 250% profit margin.

  Other Websites may have manuals not there. One example is All About Photographic Lenses, though some of the links appear to go to a Russian Website. ;-( Some manuals may not be free so make sure that a free download site hasn't been overlooked. Even so, sometimes there are enough free "Preview" pages to be useful. Or the typical cost of under $10 may be worth it if you are really serious about tackling a dicey repair.

  Another is ElectroTanya, which has manuals at present elsewhere. And it (as of early 2026) is currently free for up to 10 downloads/day.

  However, beware of suspicious links - it's not worth the risk of infecting your computer. ;-( If your browser or AV software raises a red flag, stay away!

• Manuals from Nikon direct: Nikon (the company) has started up a Website with free repair information on some specific newer photo gear including Z cameras, lenses, and accessories. (This is totally separate from and in addition to their repair services.) But like the other service or repair manuals on-line, at best these are also only "disassembly" and "reassembly" manuals as there is absoulately No troubleshooting information. They share a similar style with the others, but may have slightly fancier drawings. ;-) Model coverage is rather hit or miss at the moment, and even for those that are there, some have little that is useful. For example, there is comprehensive informatiion for the very boring FTZ-II Z-Mount to F-Mount adapter, yet almost nothing on the Nikkor Z DX 16-50mm f/3.5-6.3 VR lens. Some of the Z cameras and Z lenses are covered in great detail, but may also leave out some key steps. For example, in the case of the Z6III, that would appear to include any disassembly below the level of the front section which includes major parts like the image sensor, IBIS (In Body Image Stabilization), and mechanical shutter. But they are better than nothing. And at the very least should be useful to satisfy your curiosity. See: Nikon Self-Service Repair.

Selecting a Type of Digital Camera

1. Smart phone cameras: If you don't care and don't want to care about the mechanics of taking pictures, use your phone camera. With each successive generation of smart phones, their built-in cameras improve dramatically and provide remarkably good picture quality and features often not available in expensive gear. Due to the mass appeal of smart phones, a great deal of engineering effort and money is put into their design really pushing the state-of-the-art - which in some cases would appear to violate the laws of physics given the teeny lenses and sensors of phone cameras. While there are far fewer options when taking pictures, the default set is often perfectly satisfactory. There may even be some that are not commonly available with stand-alone cameras. And while it is sometimes possible to access features like shutter speed that are normally hidden, that will probably be awkward and only revealed with a Web search. Don't expect to be able to print huge blowups though - the appearance of qualtiy may fall apart quickly. These are optimized for the small screen. So while some phones claim 50 M-pixel (or more!), that will not provide the same quality as a 50 MP DSLR or mirrorless camera. The pixel size on that phone camera sensor is similar to the wavelength of visible light! But your phone is likely to be with you at all times so there are no issues of lugging around 10 pounds of extra photo gear.

2. Point-and-shoot cameras: These are the next step up incorporating many features of "real" cameras like the ability to control shutter speed and aperture and other photo-geek parameters. ;-) The reality is that in most cases, they will be used in "automatic" mode. For 99% of your photos, the quality will likely be comparable to those from an expensive DSLR or mirrorless camera. And they fit in a pocket and weigh only a few ounces. The typical point-and-shoot camera will have 6:1 to 10:1 optical zoom which for a DSLR would mean a bulky zoom lens with the rig then weighing in at 2 to 3 pounds or more. They will also have a macro (close up) capaility built-in typically being able to focus within an inch or less of the subject. A full size camera would require a separate pricey macro lens or a set of closeup lenses that screw on the front of the standard lens, yet another hassle to carry around and install when needed.

3. DSLRs or mirrorless cameras: Of course for professional photographers it is essential to have control over EVERYTHING. (Or to at least be able make that claim!) And while these will have various automatic modes, full control will be possible (if rarely used in practice). The potential picture quality can be better due to the large sensor - that's simply the reality of the laws of physics (though modern phone cameras do appear to be violating some of those laws). In practice it may only matter for super huge blowups.

   Note: One would think that when shooting with a DSLR in "live view" mode (which uses the sensor with the mirror up) it would behave like a point-and-shoot and be silent if the simulated shutter sound is turned off. But this is usually not the case for technical reasons having to do with the way the sensor reads out data: The mirror flips down and the mechanical shutter closes, then it opens for the exposure and closes after the exposure, and then the mirror flips up, and the shutter opens. That's why the entire sequence of events when pushing the shutter button takes a lot longer and is noisier with live view. Try it! ;-(

   Mirrorless cameras are essentially the professional versions of point-and-shoots with a high resolution LCD viewfinder instead of an optical viewfinder (in addition to the normal LCD display) both fed from the main sensor. And a price tag 10x to 100x higher. ;-) Having said that, mirrorless is where manufacturers are putting their R&D effort now with no future offerings likely in DSLRs. And having now experienced Mirrorless, I can say with certainty that budget permitting, you won't want to go back to a DSLR.

In the end, the quality of your photos will depend more on care in composition, lighting, a steady hand, and other factors not part of the camera itself. Technology can help but it doesn't replace these. No matter the cost of the equipment, if the lighting is not balanced or the depth of field is too shallow, the photos will be poor.

And as a practical, with high-end photo gear having so many options, there are many more ways to screw up the resulting photos. Even the default out-of-the-box settings (e.g., "Program" or "Auto") may result in photos inferior to those from your phone or $100 Point-N-Shoot.

40+ years ago I owned top-of-the-line Nikon film SLRs including the flagship Nikon Photomic FTN body with several Nikon fixed focal length lenses. Zoom lenses were a pricey extravagance back then. The FTN body alone was around $350 in 1970s dollars, which would be comparable to roughly $2,000 now accounting for inflation. In those days the only assistance was the built-in exposure meter. Focus and aperture were manual. I did my own darkroom work and ended up with a few good pictures and a lot of mediocre ones. Nowadays I have several low-mid level Nikon DSLRs purchased for either $500 new (D5600) or much much less than that on eBay (D70, D80, D3000, D5200, etc.) and several lenses, but what I had been using most before the development (no pun) of this document was a Canon SX710HS point-and-shoot, primarily for Website photos. It was around $100 on eBay several years ago. A Nikon D70 (one of two each for $10 on eBay excluding lens but including shipping) has been used for many of the DSLR and lens dissection photos later in this document, but it's not clear if the resulting photos are really any better on average than using the Canon. I now use a Nikon Z6III which make all my DSLRs feel like toys, but most of the photos are still probably not arguably better in an A-B comparison. FWIW, the Z6III does proabably represent the "sweet spot" in the Nikon Z lineup with the slightly earlier Z6II a close second. The Z7II has a higher resolution sensor (45 MP versus 24 MP) but appears to be otherwise similar to the Z6II - they share the same instruction manual. And the Z8 and Z9 are just over the top for the needs of most non-professional photographers.

So start out with your phone. If that proves to be too limiting, try an inexpensive point-and-shoot and explore its more advanced capabilities. After that, consider a low-end or older DSLR. One doesn't need to spend many hundreds or thousands of dollars to get started. As noted, many of the photos linked from this page were taken with a Nikon D70 picked up on eBay for $10, with various zoom lenses, typically around $25. Add a battery, charger, and neck strap, and the entire outfit was less than $50. Getting deals like that take some effort, patience, and luck. ;-) But a camera with a "standard" or "kit" autofocus zoom lens and other required accessories that provides many features of more expensive ones can be had for $150 or less on eBay. Use that for a while and see if its benefits outweigh the hassle of lugging around several pounds of photo gear. And like boating, serious photography can end up becoming a money pit. ;-( ;-)

About the Photos Linked from this Document

• Many of the photos were taken with an ancient Nikon D70 in keeping with the historical value of some of the material here. This is especially fitting for the D70 dissection. ;-) In that case, a Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G zoom lens was generally used for the camera dissections. For the lens dissections, the same model lens was used on the camera in many cases, set at 55 mm. A Nikon Micro Nikkor AF-S 40 mm f/1:2.8G lens was used for the extreme closeups. The camera was of course on a sturdy tripod. Along the way I moved up to a D90 and then used my D5600 for some (mostly the later lens dissections) And finally, starting with the Z 16-50mm f/1:3.5-5.6 dissection, to the Z6III. But I would challenge anyone bothering to pay attention to be able to identify which photos were taken with which camera without checking the metadata.

• Illumination was originally a pair of 100W equivalent LED bulbs in a gooseneck desk lamp for overall lighting with fill flash for most shots. Initially, a blue surgical towel was the background, but later a white cloth and then a piece of white poster paper was substituted for it. Then the camera was set to overexpose by ~1 stop when needed to bring out detail in the black parts and (mostly) bleach the background. The camera was set for Aperture priority at f/18 for a decent depth of field with minimal degradation from diffraction effects. Definitely not perfect but satisfactory short of putting together a professional photo studio.

  Later on, semi-antique ;-) 75 watt genuine incandescent lamps were substituted for the LED bulbs with the camera's "White Balance" set to incandescent and no flash. This appears to have better color redition requiring less fiddling with corrections. The D70 was usually set to Manual at f/18 except for some extreme closeups where even greater depth of field was desired.

  Sometimes there will be subtle blueish highlights in the photos. While that adds character, what it really means is I forgot to turn off the ceiling daylight or cool white T40 fluorescent replacement LED lamp when shooting. ;-)

  And still later, a ~16x16 inch LED fixture with a diffuse cover was suspended above the shooting area to provide more uniform illumination. This usually works well at f/16 and 1/6th second with the "film" speed set at ISO 200 and the white balance set to "auto". There is usually little or no need for post adjustment. My eBay camera and lens listing photos currently use this setup.

  A very few shots were taken with a Point-N-Shoot Canon SX710HS, usually where the bulk of the larger camera was a hindrance. They were mostly hand-held with flash. Again, see if you tell which are which. ;-)

  I've not found a simple ideal shooting setup. In short, my mileage may vary, as will yours. ;-)

• For the early parts and dissections photos, the inPixio On-Line Background Removal Tool was then used where applicable. The Web version is is currently free without any obvious limit on the number of photos processed, though for how long it remains free is not known. While multiple photos can be uploaded as one operation, the backgrounds must be removed individually. But that's just a matter of selecting the photo and saving it. For the most part, inPixio worked without issues but in a very few instances it got totally confused, usually removing more than it should have. So some manual editing may still be required. ;-) There may also be a bug in inPixio that causes it to use the wrong name for the first or last photo loaded if previous photos are present - or even if they have all been deleted on the inPixio page. So it may be best to refresh the inPixio Web page before each batch of new photos is uploaded. And that's a much faster way to clear out a large batch of old ones than doing them individually. ;-) But the first photo loaded even having done that may be wrong. ;-( I have pointed this out to them via their Feedback form.

  inPixio produces PNGs with transparency for the (removed) background by default which then appears black and there doesn't appear to be a way to change that in the on-line free version, so XnConvert Batch Converter was used to generate JPGs with a white background. The filename option should be blank so as not to add extraneous junk to it. For one at a time, MSPaint or something similar can do the conversion. But some will preserve the transparency which may be undesirable.

  Note: As of sometime in 2023, the free version of Inpixio has become next to useless since it limits image size to 640x480. I don't have a recommendation for a decent free background remover tool. If anyone knows of one that isn't likely to switch to a paid subscription, please contact me via the Sci.Electronics.Repair FAQ Email Links Page. Or just make sure you shoot with a nice background. ;-)

  With the current shooting setup, background removal is no longer considered to provide any real benefit. So it is not used and the occasional slight shadows simly add character. ;-)

• For the collections, Web Album Generator was used and set for "Extra Large (1024 x 768) pixel resolution which limits the size to not exceed 1024H and 768V. (However, this appears to be not quite bug-free. Or more likely, I just don't understand their algorithm.) Yes, Web Album Generator has a rather archaic idea of what "Extra Large" means. ;-) Most of the photos were taken at 3Kx2K resolution even where the camera could do 6Kx4K. The higher resolution was used occsianally as a cheat to get a closeup shot without using a closeup lens. These were then cropped and sometimes scaled so the resulting file wasn't too huge. These cropped originals are usually available in the same folder as the Album and may be accessed by copying the title of the photo at the top of the page (not the filename created by Web Album Generator) and adding a ".jpg" to it. If that's not high enough resolution for you, contact me and ask nicely. I may be able to provide the original(s).

• Cropping, rotation if needed, as well as adjustments like color correction, gamma, brightness, and contrast were done using IrfanView. In a few cases where these is supposed to be absolutely no color in the photo, it was converted to pure grayscale.

• Any photo editing including adding captions and such was done with the Win 7 version of MSPaint. (The last time I tried to use the Win 11 version, it had annoying quirks.) And yes if one looks carefully, there is a small amount of touch-up to improve the aesthetics of a very few photos. Sorry. ;-) I have tried Photoshop-like programs but they are so over the top with capabilities ("creeping featurism" is what we called in when developing hardware or software) as to be too cumbersome for doing simple things. ;( ;-)

• The individual photos (with the DOS-compatible filenames) are part of the Sci.Electronics.Repair FAQ distribution but the Web Albums and their photos have long names and are not.

• For the dissections, multiple lenses of the same model may have been used at various stages of disassembly. This means aesthetically pleasing samples for the exterior shots and expendable certifiably broken ones for the innards since the likelihood of restoring them to working condition would be miniscule after discombobulation.

Links to All Web Albums

Note that most of the photos in the Web Albums are at a quaint resolution of only 1,024 pixels horizontally. However, nearly all of the photos are available at somewhat higher along with their EXIF data by copying the name of the photo displayed at the top of the screen just below the thumbnails and appending a ".jpg" to it in the same folder. So for example, in the "Nikon AF-S DX Nikkor 18-300mm f/1:3.5-5.6G VR Zoom Lens Dissection" at repairfaq.org, to view the photo titled "AF-S-DX-18-300mm-f3.5-5.6G-ED-VR-Right_Front" at full resolution, replace "index.html" in the folder path: https://www.repairfaq.org/sam/reppic/Nikon_AF-S_DX_Nikkor_18-300mm_3.5-5.6G_VR_Zoom_Lens_Dissection/index.html with "AF-S-DX-18-300mm-f3.5-5.6G-ED-VR-Right_Front.jpg" and display it. Then to view the EXIF data which includes the specific camera, lens, and other settings, save it to a convenient folder and open it with a program like IrfanView. The EXIF data is under: "Image", "Information". This photo was taken with a D5600, zoom setting of 55mm, 1/2 second exposure at f16. Evem higher resolution versions (cropped from the original) may also be available. Contact me via email link if interested.

Cameras:

• Nikon D70 DSLR Dissection Web Album.
• Nikon D80 DSLR Dissection Web Album.
• Nikon D3000 DSLR Dissection Web Album.
• Nikon D5300 DSLR Dissection Web Album.

Lenses:

Note that the terminology (mostly in the photo titles) may not be quite consistent. Specifically, the terms "Lens Group" and "Lens Cluster" may be swapped. Sorry, I'm not going to correct it for a zillion photos. Further note that my designation of "Lens Cluster" in itself may be unique. ;-)

Definitions:

• Lens Element: An optic consisting of an indivisible piece of glass or plastic.

• Lens Group: A collection of one or more Lens Elements, usually secured with adhesive in the latter case.

• Lens Cluster: A collection of one or more Lens Groups that form an assembly that moves as a unit within the lens when the Focus or Zoom setting is changed. Typically this will be a Lens Cluster which moves for focus, or one which moves when Zoom is changed and may also include the aperture and/or vibration reduction mechanisms.

For example the AF-S DX 18-55mm VR II "kit" Lens has 11 Elements in 8 Groups in 3 Clusters. See the Lens Architecture and Lens Group Positions diagrams (3 and 4) in the Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album. The Front Lens Cluster moves to adjust focus as well as when Zoom is changed. The Middle Lens Cluster moves with Zoom and includes the vibration reduction and aperture mechanisms. The Back Lens Cluster moves with Zoom. There's pretty fancy footwork going on even in this very basic lens, especially for Zoom! ;-)

Nikon F Lenses

• Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED II Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Parts Web Album.
• Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album.
• Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Parts Web Album.
• Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR II Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens Parts Web Album.
• Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-200mm f/3.5-5.6G VR Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-200mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-300mm f 3.5-5.6G VR Zoom Lens Dissection Web Album.
• Nikon AF-S DX Nikkor 18-300mm f 3.5-5.6G VR Zoom Lens Dissection Web Album.
• Nikon AF-P DX Nikkor 70-300mm f/4.5-6.3G ED Zoom Lens Dissection Web Album.
• Nikon AF-P DX Nikkor 10-20mm f/4.5-5.6G ED Zoom Lens Web Album.
• Nikon AF-P DX Nikkor 10-20mm f/4.5-5.6G ED Zoom Lens Dissection Web Album.
• Nikon AF-S FX Nikkor 28-300mm f/3.5-5.6G VR Zoom Lens Dissection Web Album.

Nikon Z Lenses

Unfortunately for our purposes, even totally worthless waterlogged or mangled Z lenses go for real money on eBay, so there will likely be only limited opportunities to acquire these for dissection. ;-(

• Nikon Z Nikkor DX 16-50mm 3.5-6.5 VR Zoom Lens Dissection Web Album.
• Nikon Z Nikkor DX 50-250mm 4.5-6.3 VR Zoom Lens Dissection Web Album.

Miscellaneous:

• Copal Square S Focal Plane Shutter Mechanism.

Wanted: Nikon Photo Gear in Any Condition

Specific Nikon DSLR Camera Models

Nikon D70 DSLR

Nikon D70 DSLR Dissection

There is a D70 repair manual on-line. Search for "Nikon D70 Repair Manual PDF". It has many detailed photos with step-by-step disassembly and reassembly, some explanations, and parts identification.

I've actually come to like this camera despite having owned top-of-the-line Nikon F film SLRs many years ago as well as the newer D5600 and other D5xxx DSLRs. While the D70 is heavy and clunky (politely perhaps referred to as more "Solid") compared to newer Nikon DSLRs and has limitations, it is relatively simple to use with no excessive creeping featurism, excellent battery life since nothing is really running until the shutter button is pressed as there is no power hog live view mode, has a fast shutter response, and, uh, also takes decent pictures. ;-) This one has a shutter count of around 12K, so it's really only a teen as these things go. ;-) See my general comments on a "Selecting a Type of Digital Camera". You may be surprised at my conclusions.

The photos may be viewed at: Nikon D70 DSLR Dissection Web Album. (This opens in a single new tab or window depending on how your Browser is set up.) Some of the photos may be rather gory. So send the kids and pets to another room. ;-) These shots start with an intact camera similar to the one being discombobulated, and then the core, various covers (including the back one with the LCD), the microcontroller PCB - essentially almost everything that can be detached with only the use of a screwdriver and by unplugging cables. Reassembly would be straightforward, at least in principle with adequate notes, closeup photos, and some luck. Beyond this point, except for removing the CCD assembly, wires have to be unsoldered or cut. As can be seen, this has now commenced as the necessary chants and incantations to the gods of dead cameras have been issued and notarized. ;-) And yes, a close examination of the photos will reveal that a pair of buttons did disappear before they should have during the disassembly and I didn't notice. Live with it. ;-)

And as noted in the introduction, to complete the circle, the photos were taken with another D70. ;-)

Here are the descriptions:

• D70 Overall Views: These first dozen or so are simply boring shots of an original intact D70, so skip them if you already know what it looks like. ;-) I don't know why I called then "Overall" views and not intact, clothed, or undiscombobulated, but I'm too lazy to change the names on all of them. ;-)

• D70 Front, Back, Bottom Views: Shots of the D70 after its outer clothes have been removed - almost everything that can be detached using only a #0 Philips screwdriver without cutting or unsoldering wires except for the CCD sensor assembly.

• D70 Backplate Front, Back: This detaches with just a few screws and ribbon cable. It includes the back-lit LCD for the menus and photo display, various buttons and switches, and the door for the Compact Flash memory card slot.

• D70 Bottom Cover Outside, Inside: Pretty boring. The only thing of note is the long structural metal piece with the 1/4-20 tripod mounting hole.

• D70 Bottom PCB CPU, RAM: This appears to be the brains of the camera and is attached using only screws and ribbon cables. The large square chip is probably a custom Nikon microcontroller while the long ones are RAM.

• D70 Parts 1: Group shot of the core and almost everything (except the CCD sensor assembly) that can be removed without cutting or unsoldering wires.

• D70 No Top Front Up, Back Up: Views looking down with the top assembly removed.

• D70 Top Top, Top Bottom, Top Bottom PCB: The, uh, top and bottom of the top. ;-) The function of the PCB is not known, though the blue-taped solenoid barely visible beneath it is the flash pop-up release.

• D70 Back, Shutter: Views of the back of the camera with the CCD sensor assembly removed revealing the focal plane shutter.

• D70 CCD PCB, CCD Sensor Straight, Tilt, Angle: Views of the 6 MB CCD panel and its control PCB.

• D70 Power PCB Top, Bottom: This is the PCB on the bottom of the camera and appears to be for providing the various voltages needed to operate the camera from the battery input.

• D70 Mirror Box Left, Back Left, Back, Back Right, Right: Views of the mirror box with shutter attached.

• D70 Mirror Box Bottom Left, Inside, Bottom Right: Views of the mirror box with the shutter removed. The main mirror normally at 45 degrees except when actually taking a photor is not 100% reflecting but allows a portion of the light to pass through to another smaller mirror at -45 degrees which reflects it down to yet another mirror that reflects it to a sensor. This is used by the autofocus system so it can monitor exactly what is happening with the main mirror in the down position.

• D70 Mirror Up Left, Front, Right, Back: Views of the mirror box with mirror locked in the up position. This would only be used when exposing the CCD while a photo is being taken, or (in the D70 since there is no video mode) when manually locked up for CCD cleaning.

• D70 Shutter Front, Back, Open Partial, Open Full: View of the shutter assembly. Note that unlike most other DSLRs including more modern Nikons, the mechanical shutter apparently does NOT control exposure - that is done electronically via read out of the CCD. So in normal operation, it will either be fully closed or fully open. A solenoid opens and closes the shutter depending on the voltage polarity. Around 5 V is more than enough to activate it. ;-) There are several other sets of connections to the shutter, purpose unknown.

• D70 Controls + LCD Top, Bottom: The top shows the exposure information LCD and its PCB, the "AF Assist Lamp" (an incandescent light bulb) in its reflector, contacts for the power switch, and shutter release button switch. The bottom shows the PCB associated with the LCD (and who knows what else) and the incremental encoder patterns for the two wheels. The small separate PCB is believed to be for the electronic flash capacitor capacitor charging circuit and includes the inverter transformer for the high voltage.

• D70 AF Assist Lamp: This is a close up of the incandescent bulb in reflector clearly showings its coiled filament. Although not obvious in the photo, the glass envelope appears to be visibly darkened in this likely high mileage camera. The D5300 still used an incandesnt bulb but in the D5600 it's a high brightness LED.

• D70 Top Flash Exposed, Flash Exposed, Flash Close: The xenon flashlamp is at the bottom with the blue wire to the trigger transformer (wrapped in yellow tape) above it. The orange wire is probably connected to the positive of the energy storage capacitor (though not directly as that wire is pink) with the white wire being switched by the energy-conserving circuit. Or vice-versa. ;-) The black wire is negative, used as a ground return for the trigger pulse.

• D70 Motor Gears Top, Bottom: This is the main motor that moves the mirror up and down via one of its gears that drives the large white gear visible in several of the shots of the mirror box.

• D70 CF Card Housing Front, Back: This PCB is basically a means of connecting the CF card connector to a ribbon cable.

• D70 Main Frame Front, Back: Basically what's left over. ;-)

• D70 Parts 2: Everything that makes up this camera except the covers in Parts 1 and a trillion or so tiny screws and other itty-bitty hardware bits. ;-)

Nikon D70 DSLR Brain Transplant

First, the battery was removed since various pins on the connectors will be live even if the camera is OFF. The high voltage on the electronic flash components should not be anywhere near this area of the camera so that should not be a concern. The PCB on the bottom of the D70 has the main microprocessor, non-volatile memory, and RAM. The firmware is probably stored in the 29LV160TE 16M bit flash memory IC next to the chip with the Nikon label. So in principle, it could be swapped, but that's above my pay grade. ;-) Replacing the PCB is only a matter of screws and connectors. And the donor PCB had already been removed from its host during the dissection. Of course, nothing is ever quite so simple as there are at least a half dozen screws of several different lengths and their heads look identical, so either (1) care must be taken to arrange the screws in the correct relative positions after each is removed or (2) they can be compared to the unmodified D70. All the screws around the perimeter of the bottom cover must be removed along with the one on the bottom of the front lens housing, but not the inner ones that secure the metal base/shield inside the cover. Then cover can be angled up and slid off of the USB connector on the PCB.

There are 5 ribbon cables that need to be unplugged. For all except the large one at the end next to the Nikon chip, the black fasteners flip up; for the remaining one it slides out. If a wrong move is attempted something may break and it may not possible to assure the cables make good contact with the connector pins. Once the fasteners are released, the cables will slide out. The 4 large-head silver screws securing the PCB can be removed and the PCB will unplug from a white connector underneath and slide out of the USB housing.

Reassemble in reverse order. There are one or two cushy gray conductive pieces that technically should be replaced but they popped out when the PCB was removed and I could not determine where they went. So be it. ;( ;-) Taking the bottom plate off the other working D70 to check is not going to happen.

After reassembly, it was possible to upgrade the firmware so the 2 working D70 are now similar.

Then I was looking at the camera and realized that the reason the firmware would not upgrade was probably that it was actually a D70S, NOT a D70, though the V1.00 firmware may still have been out of date. There is no on-line way to upgrade the D70S firmware even though it appears as though the current revision may be something like V1.30. And some further digging revealed that the D70 V2.00 firmware is probably very close to the latest D70S firmware. So if that being totally confusing, it's staying the way it is until a reason appears to justify ripping the camera apart again. ;-) Since all functions I've tested seem to work with the D70 brain board (with V2.0 firmware) in the D70S camera, my conclusion is that there is no difference in the firmware.

The Franken-camera appears to work correctly and the photos look similar to the those from the other D70. However, what is not known includes whether there are actual physical differences between the D70 and D70s, and if there is a CCD defect map stored in a chip on the mainboard, which case it would not match. Nothing obvious has appeared but who knows? Most of the pics linked from here were taken with this camera so it appears to work well enough. ;-)

But a while later when attempting to set up a separate LCD monitor for viewing the photos after shooting, this camera does not recognize that a video cable is plugged in while an original D70 worked as described in the manual. It is not known whether this is a preexisting condition, damage caused by the transplant, or something else. Since the video plugs directly into the brain board, which is from a D70, it should behave like a D70. Lack of video is not a great loss though since the output from the camera is low resolution with mediocre quality and would be just barely useful anyhow - perhaps to confirm that the picture is framed correctly but not much else.

Nikon D70 with Corrupted Memory Data

Don't panic as the previously recorded photos should still be present. But a suitable USB memory card reader may be required to recover them. Multi-format memory card readers are available for a few dollars on eBay and elsewhere if your PC doesn't have the capability built-in. Confirm that the model you select supports the memory card format! Many may not support the old CF format of the D70. Write capability is not necessary as it should be possible to format it in-camera, or in a Canon camera ;-) if that doesn't work. Formatting is recommended after the photos have been recovered to assure the card's file system is not corrupted.

Nikon D80 DSLR

Nikon D80 DSLR Dissection

There is a D80 repair manual on-line. Search for "Nikon D80 Repair Manual PDF". It has many detailed photos with step-by-step disassembly and reassembly, some explanations, and parts identification.

The $25 D80 selected for the tearup has problems with the gears driving the mirror and displays "Err" in the top LCD after valiant whirring attempts to reset it. This is repairable based on various Web videos, but requires an almost total teardown ;-) of the camera to be able to replace the motor assembly and/or large white gear. So while the tearup will reach that point, reassembly is probably not going to happen. ;-)

All photos were taken with the same D70 used for its portraits. ;-) I do have a working D80 but that may eventually be sold. Since its shutter count is over 66K, adding to that was not desirable. The shooting conditions are similar to those for the D70 with the same settings for Web Album Generator.

The photos so far may be viewed at: Nikon D80 DSLR Dissection Web Album. (This opens in a single new tab or window depending on how your Browser is set up.)

Here are the descriptions:

• D80 Overall Views: These first dozen or so are simply boring shots of an original intact D80, so skip them if you already know what it looks like. ;-) And like the similar D70 photos, the names are what you get. ;-)

• D80 Front Views: After the first level of clothes removal, here is what's visible from the front. Note how the mirror somehow ended up in a middle position somehow, not up or down. ;-(

• D80 Back Shield Views: After the first level of clothes removal, here is what's visible from the back, which is mostly not much - a metal shield.

• D80 Bottom View: Not much here, unlike the D70 with its Power PCB or more modern cameras with the magic red gear. ;-)

• D80 Backplate Outside, Inside: Note the much larger LCD for menus and photo review.

• D80 Bottom Cover Outside, Inside: I'm guessing the gray finish is conductive.

• D80 Back and Left, Up, Right: The only difference compared to the Back Shield Views is, uh, the removal of the shield. The large PCB is believed to be the camera's brain.

• D80 Back No CCD: Here, both the brain PCB and the CCD assembly attached to it via a pair of soldered min-coaxial cables have been removed revealing the focal plane shutter as well as a smaller PCB on the right and what is probably the replacement for the D70's Power PCB on the left. The CCD assembly mounts via the three holes with the large silver surrounds. The upper left one had a thin brass washer under the CCD mount.

• D80 Control PCB + CCD Front: These are as noted attached via a pair of soldered mini-coaxial cables. Other signals and power are connected via several ribbon cables.

• D80 CCD Front Close, Tilt: These views of the CCD shows what appear to be the various wire bond connections. The heads-on Close view has a fuzzy reflection of the camera taking the photo.

• D80 CCD PCB: The mini-coaxes are clearly visible at the bottom.

• D80 Control PCB Front, Back Close: This PCB includes several Nikon chips as well as a couple from Sony. ;-)

• D80 Parts1: Most of the components that have been removed except the large shield which would just mess up the aesthetics. ;-). Also the piles of screws, ribbon cables, and other tid-bits so far. That rainbow pattern appears on the CCD when the flash is used and under some other undetermined lighting conditions. Weird.

• D80 Top Inside: What appears when the top is removed.

• D80 Top Top, Top Bottom: The bottom view shows the blue tape covered flash pop-up solenoid, the direct wiring to the flash itself, and the chip that deals with the control cluster including the encoders for the wheels.

• D80 Left PCB:

• D80 Right PCB: This appears to be for power control and conditioning.

• D80 Mirror Box: Several views with shutter (and motor) attached. Still working on how to remove the shutter. ;-)

• D80 Mirror Shutter Motor + Gears Inside, Outside: The gear train is to reduce the speed and increase the torque. The pinion gear on the motor shaft is cracked so it slips.

• D80 Mirror Shutter Cam Gear: This is driven by the motor gear train. An absolute encoder keeps track of this gear. A pair of rollers (one is visible) on the "Y" yoke above the gear are what move the mirror and cock the shutter by following the cam.

• D80 Mirror Box No Shutter Front, Back: The mirror is back in the down position. ;-)

• D80 Mirror Shutter Linkage: This is part of the mechanism which moves the mirror and opens the shutter.

• D80 Shutter, Back + Cover: The copper cover partially surrounds the shutter mechanism. It's not clear what function it really performs as there is no seal either physical or electrical and large areas are not protected at all. The two solenoids are clearly visible along with the return springs. (More below.)

• D80 Shutter Front, Back: The shutter was secured to the mirror box with 2 screws and connected by a half dozen wires. The shutter gets cocked by the same mechanism that moves the mirror. So with the mirror in the up position, the shutter is ready to fire.

• D80 Shutter Mechanism Outside, Inside: There are a pair of solenoids (visible in the "Outside" photo). Presumably one opens the shutter by dropping the lower curtain and the other closes the shutter by dropping the upper curtain. For slow shutter speeds the timing is such that the shutter opens fully. But for faster shutter speeds, the "close" solenoid is activated with a precise delay after the "open" solenoid. Originally, I was thinking there was something more sophisticated involved like binary-coded stops so the spacing could be digitally-controlled. But it all appears to simply precise timing.

• D80 Shell Front, Back: What's left. ;-) The Power PCB and other tid-bits are still installed since I didn't want to unsolder the wires.

There may be more photos to come.

If what you want is entertainment with a bit of useful information, check out the YouTube video Prime Studios - Destroying a Nikon Camera or Web page with still shots PetaPixel - Step-by-Step Teardown of the Nikon D80 Shows You What's Inside a DSLR. Thankfully, both of these are the same D80 and it had already been fatally damaged before he got a hold of it, so the gore is tolerable. ;-)

For the specific problem this D80 has, namely the whirring gear error, there are a pair of more serious YouTube videos at Nikon D80 ERR Split Gear Part 1 which covers the disassembly to access the gear motor and Nikon D80 ERR Split Gear Part 2 which covers the installation of the replacement and then reassembly of the camera. And of course since there are a lot of shots of the camera in various stages of discombobulation nearly to the bare bones, it also serves as a decent dissection, though attempting to keep track of what screws were removed at each step may be rather challenging.

For this camera, the black gear attached to the motor shaft is indeed fractured so the motor spins with fully doing what it's supposed to do, but whether that happened on its own or was the result of excessive torque driving the mirror / shutter mechanism due to some other issue such as a faulty encoder position sensor is not known and I'm not really inclined to go to all the trouble of replacing the gear and reassembling the camera to find out. Sorry. ;-) Though the expense at least wouldn't be much as the gear in my dissected D70 is the same. Even if I didn't have that, there are over 100 listings on eBay for the gear, some under $3. It must be a common failure. And for someone with an attention to detail in keeping track of everything during disassembly (especially the locations of the solder joints for the dozen or so wires that need to be disconnected), repair should be straightforward if not cost effective. ;-)

And to top it off, I accidentally removed the motor mount (not just the motor and gearbox itself via the two large-head screws) and lost one of the rollers without even realizing it until the mirror would not come all the way down. Miraculously, I did find the roller later on the workbench and reinstalled it, but that's the reason why the mirror is in the fully up position in the Mirror Box photos rather than down as would have been preferred. ;( :-)

Nikon D3000 DSLR

Nikon D3000 DSLR Dissection

Coming soon. Photos of an intact D3000 may be viewed at: Nikon D3000 DSLR Dissection Web Album. (This opens in a single new tab or window depending on how your Browser is set up.) But that's so boring.

Nikon D3000 with Dead LCD

There is an internal flex cable running from near the center of the back panel assembly inside the rear cover of the camera to the LCD itself. It attaches to a "zero insertion force connector" - the ones with the thin lid that has to be flipped up to insert or remove the cable. In this case the cable is short and just barely reaches the connector. So even though additionally secured with a piece of tape, it apparently pulled out over time or more likely was never inserted quite correctly in the first place as that is a bit challenging. Voila, nothing on the LCD, only the back-light.

The rear cover of the camera is secured by 2 screws on either side, 2 screws near the viewfinder (partially hidden by the rubber eyepiece cup if present), 4 screws along the back edge of the bottom, 1 screw further in, and 1 screw under the rubber cover next to the battery compartment latch. There are several different size screws so make sure to set them aside labeled as to their origin. Once the screws have been removed, the rear cover can be popped off, perhaps with the aid of a thin blade. CAUTION: It is connected to the main board via another zero insertion force connector near the bottom so take care not to rip it.

With the rear cover separated from the body, the problem will be obvious. Remove what's left of the small piece of tape, flip up the latch, and carefully insert the cable so that it extends underneath the edge of the connector as far as it will go, and then flip the latch down. Then add a larger piece of Kapton or similar tape to help secure it. Or a bit of 5-Minute Epoxy. Camera operation can be carefully confirmed with the back in place but before installing the screws.

Nikon D3000 SD Card Door Replacement

There are 4 sizes/types of screws and of course the same type of each needs to goback where it came from. ;-) These are: short, medium, long fine thread, and long coarse thread. But don't panic if the 2 types of long screws get mixed up, just try to get them back in their place. As with all camera and lens repairs, a high quality 00 or 000 Phillips screwdriver is a must. It may be possible to do the replacement without removing all the screws as specified below but it won't hurt. The bottom cover must be loosened at the very least to allow the back to be freed up to allow the SD door cover assembly to be removed.

1. Remove the battery and SD card.

2. Remove 4 long fine thread screws, 2 on each side of the back cover.

3. Remove 2 long coarse thread screws, 1 on each side of the viewfinder.

4. Remove 4 short screws along the back edge of the bottom cover.

5. Remove 1 long coarse thread screw inside rubber trap door for the optional external power cable at edge of bottom cover next to the battery compartment (medium).

6. Remove 3 long coarse thread screws on bottom cover.

7. Remove 2 long coarse thread screws on bottom cover over lens shroud.

8. Remove 2 medium screws inside the SD card compartment.

It should now be possible to remove the bottom cover so the back cover can be lifted at the SD card-end freeing the SD card door assembly. The back cover does not need to be removed entirely, just 1/4 inch or so and in that case step 7 and possibly some others can be skipped), but if it is, take care not to tear the flex cable attaching it to the main PCB.

The SD card door assembly can now be pivoted up and removed.

Install the new one in reverse order. The screws should go back in easily, take care to avoid cross-threading any and do not over tighten - just snug.

Nikon D5200 DSLRNikon D5200 DSLR

Repair of Dead Shutter Button Etc. Cluster

There is a nice set of photos of the back removal process at iFixit Nikon D5200 Motherboard Or Camera Back Replacement.

The problem was immediately obvious: One half of the tiny black lever on flex cable connector going to the shutter button cluster was missing. This camera had obviously been opened by someone and they managed to snap it off. So, part of the connector was making somewhat reliable contact and the rest was making none at all. Pressing on the cable while simultaneously juggling the camera with three hands revealed that at least some of the missing functions had returned.

However, parts for these connectors aren't the sort of thing one can purchase at Radio Shack (even if Radio Shack still existed). I attempted to cannibalize one from a likely bad D5300 mainboard but either it wasn't the identical type or I messed up attempting to install it. which isn't surprising as these are barely visible even under magnification. And it broke into 3 pieces when putting it back where it came from. Perhaps they are available on eBay for only $99+shipping and would then break into three pieces on demand. :( ;-)

Plan B was to fashion some sort of jig to apply the required pressure to the cable. The solution consists of a piece of resilient floor tile about 3/8 inches in length and 1/8 inch square, and a piece of stiff foam to press it against the connector using the back cover when it is in place. Can you say "Kludge"? ;-) But for the most part, it appears to have worked. Most of the missing functions have returned and appear to be reliable. There are still some funny things about the camera that may be related to why the original owner went inside in the first place. Or they could just be incorrect settings though everything was reset. One of these is that normal autofocus engaged by pressing the shutter release does not do anything, only by pressing AS/AF button can autofocus be initiated on demand. Continuous tracking AF does work. And the shutter button does work halfway because the flash pops up if needed. So a bit strange.

Using a remote shutter release with the camera on a tripod works great. That's actually how most of the Web Album photos are shot so perhaps in principle, this could have a life even if it does behave a bit strangely. But for now, it lives in the VR tester rig.

Notes on screw sizes and types:

• Three short fine thread screws with sort of rounded heads secure the bottom cover.

• One short fine thread screw with a flattish head secures the back cover from under the rubber finger pad.

• Two long fine thread screws secure the bottom of the viewfinder bump.

• One long coarse thread screw secures the top left of the viewfinder bump.

• Two long fine thread screws secure the left side of the back cover.

• Two medium coarse thread screws secure the right side of the back cover. The difference in length between these and the long coarse thread screws is not much so they are easy to interchange. But Nikon in their infinite wisdom placed two screws inside the battery compartment at exactly the same location as these. If long screws are used, they may force the inner screws to push out and interfere with the battery. Then the only remedy is to use an even longer screw to push them out entirely and assume that nothing bad will happen due to their absense.

Nikon D5300 DSLR

Nikon D5300 DSLR Dissection

The photos were taken with the second working D70 / D70s following its brain transplant. ;-)

The photos so far may be viewed at: Nikon D5300 DSLR Dissection Web Album. (This opens in a single new tab or window depending on how your Browser is set up.)

Here are the descriptions:

• D5300 Views: These first ten or so are simply boring shots of an original intact D5300, so skip them if you already know what it looks like. ;-) Note the shots into the lens mount: This camera apparently failed while taking a photo with the mirror up and shutter open. And like the other dissection photos, the names are what you get. ;-)

• D5300 Backplate Outside, Inside: Since the LCD is able to flip out facing up, down, or anywhere in between, it has the white round cable that disappears inside the cover to make that possible.

• D5300 Top Top, Bottom: Stereo separation must be stellar. ;-) The object with the yellow tape is the flash pop-up solenoid. The silver tape covers the WiFi antenna.

• D5300 Frontplate Outside, Inside: On the D5300, the right hand-grip is part of the frontplate with a stick-on rubber pad (missing). The PCB is for the video and other interfaces.

• D5300 Mirror Box Many Views: Eleven shots from all angles with CMOS sensor and its PCB still attached.

• D5300 Mainboard PCB with Shield: The shield clips in place with the clock battery visible through a hole.

• D5300 Mainboard PCB + Shield: Separated.

• D5300 Mainboard PCB Front, Back: There only appears to be a single small Nikon IC.

More to come, perhaps.

Nikon D5500 DSLR

I only have a single sample of the D5500, which was purchased originally intended for a dissection since it is so close to the D5600. Whether that happens is unclear. It may be worth more intact even sick than as parts. ;-)

D5500s

• ID #1 (SN: 2656338): This is in nearly perfect cosmetic condition with a shutter count of only 6,129. There are no signs of trauma or water damage but it definitely behaves quite sick:
  • The 24MP sensor, back LCD, viewfinder LCD, back-panel buttons are known to be functional but only very occasionally, like twice in the entire time I've been playing with this thing. Under those conditions, it possible to get Menus and Live View to work and even shoot a few photos (though they were all white because there was no lens attached). But I do not know how to repeat that! Under those conditions, it could save photos to a memory card but hung after reading them a few times.

  • It does recognize CPU lenses and display their f/number setting in the viewfinder LCD, and will focus but apparently doesn't achieve focus lock and will never fire the shutter except in Manual mode.

  • The shutter generates an Err message in the viewfinder LCD (the main LCD almost never comes on). If powered up in Manual mode, pressing the shutter release will alternatively appear to fire the shutter correctly based on the shutter speed setting displayed and then produce the Err. The mirror flips up in both cases exposing the sensor, but it's not clear if the front curtain (mechanical shutter) is ever activated (it may always be stuck open). If the Live View lever is pressed with the info (not Err) displayed in the viewfinder LCD, the mirror will flip up but then drop down again and generate Err. And at some point it will forget the original shutter speed setting and revert to 30 seconds.

  • The memory access LED doesn't come on at power-up as with other Nikon DSLRs. It is not known if it comes on when storing or reading photos as that has been so infrequent (like only once so far) to notice. ;-(

    So there is some issue with the shutter. Whether that is the entire problem is unknown but is not likely as it would not explain the inability to show anything on the back LCD. It could be corrupted firmware but there may be no way to update it without access to the Setup Menu. And the UC-E6 port seems dead at least for video output (tested using the A/V cable from the D5200 on the VR tester shaker platform). Awaiting a compatible USB cable to see about PC access, but that is probably mostly dead as well.

    Nikon D5600 DSLR

    I have not found a repair manual for this camera or anything close.

    The D5600 is at the top of the "entry-level" or "upper entry-level" class of Nikon DSLRs depending on who is doing the classifying. It is apparently the last of the D5xxx series and possibly all DSLRs, with Nikon now concentrating exclusively on mirrorless cameras.

    A D5600 was actually the first DSLR I acquired after deciding to get back into more serious photography. Or at least *studying* more serious camera gear! My previous serious cameras were the Nikon F with the Photomic FTN finder and the Nikkormat. Go date those! ;-)

    • ID #1 (SN: 3206132): The first one was purchased on eBay along with an AF-P DX 18-55mm f/1:3.5-5.6G VR "kit" lens as "Nikon Refurbished" and is believed to be in perfect condition though even on only an "upper entry level" camera like this, it's impossible to really test everything. ;-) But it works well and has been used to shoot many of the dissection photos. The original shutter count was around 200, now just over 4,000...

    • ID #2 (SN: 3007593): This was purchased three or four years later on eBay as "For Parts or Not Working" along with an AF-P DX 18-55mm f/1:3.5-5.6G VR lens, battery, charger, and strap. It is not known if the lens and camera were actually originally part of a "kit" or just cobbled together by the seller. The total cost was $81.14 delivered. The lens was then resold for a net of return of $48.54. So this was essentially a $32.60 D5600. ;-) The description included that the monitor display had problems and Autofocus did not work at all. The monitor definitely had problems but ended up being very usable and the lens issue was non-existent. The shutter count was around 34,000.

      There appear to be 2 related problems with the LCD.

      1. Most of the time (initially at least), the monitor goes black when the panel is in the normal position locked in place facing back. It needs to be angled out by 20 or 30 degrees at which point the display appears. However, when in this state, the panel does not know its orientation so the image may be upside-down. If it is swung out from the closed position facing the camera without rotating it vertically, behavior is normal and certainly usable. The angle of the transition from black to normal appears to be fairly consistent as though it's a switch or sensor and not a bad connection. But having said that, sometimes it will behave perfectly normally (seemingly with greater probability as time goes on). Now it seems 100% reliable as long as it remains in the normal position. ;-)

         The position sensor is part of the hinge assembly and comunicates to the LCD and then via 4 individual colored wires and then via ribbon cable to the Mainboard.

      2. The four LSBs of the image on the monitor are stuck or not getting through so there is contouring in the display and makes for a kind of funky appearance with only sixteen intensity levels. Colors are not affected and are correct. So they are not RGB bits. This does not show up in the stored photos. D5600 #2 Monitor and Photo Compare shows a pair of simulated monitor images demonstrating the faulty behavior. (Attempting to take a photo of the D5600 monitor while taking a photo was more than I was willing to set up, though it would probably have been quicker and simpler!) The top photo on the left is what would appear on the LCD monitor from a gray-scale test chart on a computer screen, thus the curved contour lines due to subtle variations in brightness. The one on the right is the actual photo taken by D5600 #2. The bottom right photo is a ChatBot GPT creation when asked to "Show me some fruit". At least it looks like fruit. ;-) The bottom left photo is roughly how the fruit would appear on the LCD monitor. The on-line App Reduce Number of Colors was used to generate the images with contours. Their location may not be 100% accurate due to gamma correction and such, but these should provide the general idea. ;-)

      Both of these are almost certainly either due to broken traces in the ribbon cable a problem with it not being seated properly at the LCD or Mainboard connector, or a defective or unlatched connector. As a practical matter, neither really matters to me except in a purity sort of way as long as they don't get worse: (1) I virtually always use the monitor against the camera body facing backwards and (2) in many shooting situations, the reduced LCD tone-scale resolution isn't even that noticeable.

      Autofocus may indeed not lock when the lens is close to zoomed all the way in (near 55mm) in dim light but only in "Live View". When using the viewfinder, it is fine. However, this appears to be a red herring as both this lens and a known working AF-P lens do more or less the same thing on D5600 #1. I have a feeling that the seller may have actually tested the lens on an incompatible camera since the description indicated that AF did not work at all.

      But the Lock button on the lens does virtually nothing. Problems with Lock on these AF-P lenses are very common but this one is particularly severe in that in addition to not, err, locking, it also doesn't even restrict Zoom within the normal range, which can be annoying. But I cannot blame the camera for that. only a careless user! And interestingly, when I listed this lens for sale on eBay, it was purchased quickly and the buyer acknowledged that they knew Lock did nothing. ;-)

      Since this camera actually works fairly well, a dissection is probably not likely. ;-( ;-) However, if a known good LCD monitor panel becomes available, a transplant may be performed, or at least an exploratory to see if perhaps one of it's cables simply isn't seated properly. Though after investigating this further (see the next section), that may not occur unless the behavior deteriotes.

    • ID #3 (SN: 3213485): This was purchased later for $106 delivered also as "For Parts or Not Working" but is in excellent cosmetic condition and seems to work perfectly. The shutter count was around 1,660. ;-) Stay tuned.

    • ID #4 (SN: 8819461): And another one for $64.66 delivered also as "For Parts or Not Working" but seems to work perfectly. The fault leading to the "Parts or Not Working" description was that it hung attempting to display the menu. So that could still be an issue if it is intermittent or possibly due to a weak battery, which was dead when the camera arrived. Or just a red herring. The shutter count was around 12,000.

    • ID #5 (SN: 3030827): This one was $117.78 delivered also as "For Parts or Not Working". Near perfect cosmetic condition but but finally one that is certifiably defective. ;-) While the seller thought the CCD might be bad since all pictures were black, that isn't quite accurate. First of all, the D5600 uses a CMOS sensor, but that's a trivial error. It does indeed take still pictures that are near totally black even though Live View and movie recording are fine. (Both of course rule out the sensor as the cause.) The problem turned out to be that the front curtain shutter which is used for stills does not open at any shutter speed including Bulb and Timed, as well as Lock Mirror Up for Cleaning. Whatever is supposed to release it isn't activating properly so it seems to be physically stuck in almost the fully closed position - thus the "almost totally black as a thin strip of light can sometimes be seen at the top. Gentle prodding of the shutter itself had no effect. How the shutter can work correctly and reliably for Live View and movies while being consistently stuck for all other functions is not clear. Since shutter seems to try to open, at least a small anount, it would seem that the signal is present but something mechanical is getting in the way. For now though, this appears to be a decent camcorder. ;-) The shutter count was just over 9,000. Attempting to clear the shutter error has bumped it up by a couple hundred clicks. ;( ;-) So this is a youthful failure - the expected life of the front curtain shutter in a D5600 is typically 100,000 clicks. And there is NO error ever displayed as with other Nikon DSLRs: "Press Shutter Button Again" when the shutter cannot complete its action. So the microbrain doesn't even realize there is a problem..

    To restore D5600 #2 to full functionality, the plan was to swap its back (including the LCD) with the one from D5600 #5.

    D5600 Back Housing Removal and LCD Flex Cable Replacement

    My intention had been to just swap the entire Back Housing along with the LCD, not to replace the LCD panel itself. But based on the more extensive disassembly required - particularly the need to remove and replace a rubber pad and grip (or at least peel them off of the heavy duty adhesive securing them) - the adage "if if ain't totally broke, don't try to totally fix it." ;-) In the case of D5600s #2 and #5, not much would be gained. So for now at least that will await a certifiably dead D5600 (but with a good screen) to cannibalize.

    This is considerably more involved than removing the backs of older cameras like the D80 or D3000 and requires peeling off a rubber grip and pad and then re-attaching them. However, everything else is just screwdriver work. ;-)

    Tools Required

    • Small JIS screwdriver set. (The Phillips bit PH000 in a Husky mini-screwdriver set model "HD-74501V" works just fine for most Nikon screws.)
    • Plastic prying tool like a spudger, or with care, a single edge razor blade or Xacto™ knife.
    • Tweezers (to pursuade parts to cooperate or retrieve those screws that tried to escape).
    • Replacement D5600 LCD (or parts) or entire Back Housing with LCD.

    LCD Terminology

    • LCD Assembly: The entire unit including the hinge and connector.
    • LCD in Frame: The LCD Panel in its enclosure.
    • LCD Panel: The bare LCD.

    A video that includes the Back Housing removal and LCD Flex Cable replacement procedure may be found at NIKON D5600 LCD FLEX CABLE WITH HINGES REPLACEMENT |ADNAN CAMERA INFO (YouTube). It is fairly easy to understand each step and to be able to pause the video at relevant points. But since that can be annoying, key frames from this video have been archived in a Web Album at Steps of Nikon D5600 DSLR LCD Flex Cable with Hinges Replacement YouTube Video.

    Errors are possible.

    Disassembly

    1. Make sure the camera is powered off and remove the battery, memory card, and rubber eye-cup if present.

    2. Flip the LCD away from the camera and remove the 2 screws holding the swivel hinge mechanism to the camera body. Flip it back in place for now.

    3. Remove the screws on either side of the viewfinder.

    4. Peel off the upper right corner of the small rubber pad next to the Play button just far enough to see the silver screw. The spudger or blade may be required. Take care not to damage the plastic of the body. Remove the silver screw.

    5. Remove the 4 screws securing the bottom plate and take it off.

    6. Peel off the rubber grip next to the SD Card holder far enough to access the 2 silver screws securing the Back Housing to the body of the camera. The spudger or blade may be required to get started. Take care not to damage the plastic of the body. Remove the 2 screws.

    7. Remove the 2 screws behind the tripod mount (closer to the back of the camera) which thread into the bottom of the Back Housing.

    8. Remove the screws securing the Back Housing from underneath where the grip was. Remove the screws facing the top of the camera in that cavity.

    9. Remove the Back Housing: Carefully pry the back casing away from the camera body along the seem using the spludger or blade if necessary. Be gentle as ribbon cables are still attached. And don't force anything - a screw or screws may have been missed.

    10. Disconnect LCD and Button Cable: Locate the ribbon cable at the upper right (facing the camera) that connects the Back Housing to the motherboard. Release the locking tab on the ZIF (Zero Insertion Force) connector and gently pull the cables out sideways. Inspect the ZIF connector for daamge.

    That's it for the Back Housing. It could now be swapped with a replacement from another D5600 or D5500.

    The next level would be to swap the LCD panel assembly.

    1. Inspect the large ribbon cable from the connector at the bottom of the Back Housing to the LCD. If the cable seems loose or cockeyed or the latch wasn't fully latched, that may have been the entire issue causing a flakey LCD. Remedy it and check if it now works reliably by temporarily reinstalling the Back Housing with its flat cable.

    2. Remove the 2 silver screws inside the Back Housing on the LCD hinge-side.

    3. Flip the LCD out and remove the plastic hinge cover. Remove the 2 screws securing the hinge mechanism to the Back Housing. This should free up the LCD Assembly to be removed from the Back Housing.

    The entire LCD Assembly could now be swapped without going any deeper.

    1. Remove the 4 screws on the edges of the LCD panel. This should free up the back cover of the LCD to be removed.

    2. Remove the single screw at the center of the hinge which should enable the hinge cover to be removed.

    3. Remove the 2 silver screws securing the hinge mechanism to the LCD panel.

    4. The following steps relating to the 4 colored wires for the hinge position sensor. are needed only if the entire hinge assembly or LCD panel needs to be replaced, or if the sensor is defective. Where only the flex cable is being replaced, it may not be necessary to disturbe the wires.

       Take a photo of the exposed LCD to identify the solder locations of the 4 colored wires and then carefully unsolder them.

    5. Unplug the ribbon cable from the ZIF connector.

    The LCD Panel should now be free.

    Reassembly: Reconnect the ribbon cable, ensuring it is seated securely in th ZIF socket. With the Back Housing remounted on the camera but before securing it with the zillion screws, install the battery and test the camera to confirm that the LCD is working correctly and that all the buttons on the back panel are functional. Then replace the screws taking care to use the correct ones in their respective holes. Once functionality if confirmed following replacement of all the screws, reattach the two rubber pads. New or additional adhesive may be needed.

    Tips

    • Take pictures of every step to remember screw locations and sizes.

    • Warming the edges of the rubber with a hair dryer can help loosen adhesive. Use with caution so as not to melt anything. ;(

    • Be very cautious with the fragile ribbon cable(s); Tearing them will cause further problems and most are not repairable. Damaging the ZIF sockets would be even worse.

    Nikon D1 and D1X DSLR

    To bookend Nikon's line of DX DSLRs (with the D5600 being the final model covered here, above), I decided to acquire 3 D1s and 2 D1Xs to study, along with 4 of the mating NiMH battery packs and charger, and an AC adapter so the camera can be run without worrying about the battery running down. ;-) But of the 4 battery packs, 2 are probably not too bad, 1 is marginal, and the other is totally dead - tests with 0 V output and open. But these could date from the early 2000s, the fact that even 2 seem OK is probably more than could have been expected.

    The D1 was the first Nikon DSLR designed and built entirely in-house. The D1X is nearly identical, the main difference being a higher effective resolution of 5.3 MP versus 2.7 MP for the D1. But that higher number seems to be at least partially due to interpolation and not actually more cells in the CCD. So perhaps mostly Marketing. ;-) They may all use the same 10.8 MP sensor with various groupings of pixels for interpolation - perhaps 2x2 for 2.7 effective MP in the D1, and 2x1 for 5.4 effective MP in the D1X. There is also a D1H which has the same resolution as the D1 but a higher burst frame rate. These may in fact all be identical except the firmware and label. ;-)

    For all intents and purposes, anything described here should apply to the D1, D1X, and D1H. Repair manuals and parts lists are available at ElectroTanya. They are currently free to download as long as no more than 10 are done each day. I was originally planning a dissection of the D1 but the repair manual actually had many decent quality photos, so that may not be a high priority.

    The D1, D1X, D1H, appear to be the only post-1999 Nikon DSLRs using a NiMH battery pack, the EN-4 (and the MH-16 Quick-Charger). All subsequent DSLRs have used Lithium Ion batteries. A NiMH battery pack is larger and heavier for the same capacity compared to Lithium Ion, but in principle can be rebuilt using readily available inexpensive tabbed standard NiMH cells, which may be risky for Lithium Ion. NiMH batteries can be safely charged with a constant current or current limited power supply and are not likely to catch fire due to manufacturing defects or abuse. However, the battery will get warm during charging and if the temperature goes too high, an internal thermal protector will open. But that will reset when the battery cools off enough. The camera can also be run without a battery using the 9V 5A EH-4 AC Adapter, or by using a DC power supply with similar ratings and appropriate connector.

    For someone used to modern DSLRs and Mirrorless cameras, the first impression one gets handling a D1 or D1X is: "Holy crap, this thing is big, solid, and heavy." ;-) The body alone weighs in at around 3 pounds. Add a Nikkor AF-S DX 18-300mm f/1:3.5-5.6G ED VR "super-zoom" lens and the rig one needs to lug around will be close to 5 pounds.

    The next thing is "Holy Crap" the menu systems are pimitive, even more so for the D1. Otherwise they are fairly similar though some functions have moved from the D1 to the D1X although the physical buttons are the same.

    First, a pair of D1Xs:

    • ID #1 (SN: 5130866): This was acquired along with a pair of EN-4 NiMH battery packs. The camera is in near mint cosmetic condition and is occasionally fully functional, but only when it feels like it. ;-) One of the EN-4s seems healthy; the other has limited capacity but may still be usable with some refreshing. The EN-4s were first charged using a DC power supply.

    • ID #1 (SN: 5112921): This was acquired along with a battery and EH-4 AC Adapter. The battery is dead and will not charge (it tests open) but the camera appears to work perfectly. It just needs a little TLC as the rubber covering the bottom is stretched and coming loose so it was removed entirely for now.

    And three D1s acquired along with one battery and MH-16 charger. The battery and charger work fine.

    • ID #1 (SN: 5012356): Cosmetically challenged but appears to work. The focusing screen was missing, so the one from ID #3 was swapped in.

    • ID #2 (SN: 5013243): Cosmetically challenged and works but captured images are very dark and strange regardless of ISO setting. Images stored on a memory card from another camera display normally. The viewfinder housing appears to have a crack that was repaired.

    • ID #3 (SN: 5016146): Cosmetically sort of OK but captured images are always totally black. ;-( Images stored on a memory card from another camera display normally The focusing screen was installed in D1 ID #1 to replace one that was missing, being sort of irrelevant here..

    Stay tuned.

    Specific Nikon DSLR Lenses

    While there are many dozen if not hundreds of Nikon lenses, the only ones that are relevant for use with modern DSLRs will have support for AutoFocus (AF) and many will also have Vibration Reduction (VR). Of those, based on the number of lenses for sale on eBay ;-), the most common zoom lenses for use with DX format DSLRs (~2/3rd the sensor size of the FX format DSLRs or old 35 mm film cameras) are various versions of the 18-55 mm f/1:4.5-5.6G "kit" lenses followed by the 55-200 mm mid-range, and then the 18-200mm and 18-300mm "superzoom" lenses. All of these and more are covered later in this document in varying levels of detail. But they may not be covered in a totally logical order, sorry. ;-)

    It goes without saying that AutoFocus (AF) in almost any form has revolutionized photography. Anyone old enough to have used camera gear without AF will recall how much time was spent simply focusing each shot. However, depending on implementation or settings, AF can focus (no pun...) on the wrong features or just get totally confused. So it's still prudent to check each shot or at least a sample set before it's too late to do a makeover. And/or switch to manual focus or change to a difference AF mode if needed.

    To use VR or not to use VR - that is the question! ;-) Vibration Reduction (VR) may not be desirable under all conditions. Since the VR mechanism is controlled electronically, there will always be some noise and resulting jitter from the feedback loop. It's very small but not zero. In fact, if one listens closely, an audible hiss and other sounds can be heard eminating from the lens itself when VR is active, indicating that some internal part of the lens is vibrating. (This also turns out to be a simple way of determining that VR IS active and probably functional.) So some photographers prefer a lens without VR or with VR disabled when shooting on a tripod. Whether there is any real justification for this is not known. Unless using a remote shutter release or self timer, there will always be some vibration induced by the act of activating the shutter even if using "Touch Shutter" on the LCD and a sturdy tripod. And unless the shutter is totally electronic (which is not the case even with mirrorless cameras), it also creats vibration. As does the mirror in a DSLR. So even there, VR may still be a net positive.

    When the camera is powered on with a lens attacted, AF and VR are automatically initialized. Unusual sounds from the lens like multiple clicks or clunks, or a several second delay before the shutter release is active is an indication that there is likely an issue with AF or VR. The camera may still shoot after that delay, but check the quality of the pictures!

    The following are more descriptive with only a few fairly simple repairs. On a scale of 0 to 10 modern lenses like this rank around -10 in ease of repair, at least for someone who hasn't dealt with them before. ;( Anything requiring more than the simplest disassembly is almost certain to make things worse and likely result in the thing turning into a high-tech paperweight - at least the first few times it's attempted. Where manual focus doesn't work on an autofocus lens, live with it. ;-) Even being able to lubricate the proper surfaces is likely to require extensive disassembly and the opportunity to tear a ribbon cable, break a connector, or lose itty-bitty screws or other almost invisible parts. For many Nikon lenses like this, there are (supposedly) original Nikon repair manuals on-line but don't expect there to be much in the way of real help. They make many assumptions, don't even go deep into some major assemblies, and suffer from poor English translation. In addition, depending on what was disturbed, some specialized test equipment and software may be required to tweak alignment (though errors here are often buried in the "weeds" so-to-speak, resulting in very minor mostly undetectable issues. In fact it is hard to imagine that repair of a relatively low-end lens like these is ever really done by Nikon or an affiliate! And now with eBay, fully functional used specimens can be had for a fraction of the cost of the simplest professional repair.

    Having said that, there are some repairs that can be tackled without a great deal of experience and a reasonble chance of success. These mostly relate to failures that can be dealt with by only disassembling the back and sometimes the front of the lens. But that covers a large percentage of common problems. And since the disassembly to that level tends to be very similar for most of these lenses, familiarity with one will be preparation for many others.

    These include:

    • Focus (Auto and Manual) inoperative using AF-P lens on older DSLR.

      Level of difficulty: 0. This is a feature, not a bug due to incompatibility with older cameras. ;-) See the information above.

    • Replacement of the plastic Nikon F Bayonet Mount used on smaller lenses that can get damaged easily, possibly from an overzealous attempt to install the lens on a camera when it is not fully seated.

      Level of difficulty: 2. Depending on the lens model, these parts may be available at reasonable cost since this is a common problem.

    • Replacement of a bashed front lens group. *

      Level of difficulty: 1-2 depending on the specific lens. For some it is only a matter of unscrewing the lens group assembly.

    • Replacement of broken focus/zoom roller/guides in some specific models.

      Level of difficulty: 3. This is known to apply to lenses like the AF-S DX 18-55mm f/1:3.5-5.6G VR where the focus ring rotates and changes the focus directly. The required rollers also need to be available.

    • Repair of broken focus assembly in some specific models.

      Level of difficulty: 3. Similar to above but creativity in rebuilding some parts will be required.

    • Re-seating of loose flex cables.

      Level of difficulty: 1. Most cable connectors are generally accessible after removal of the Bayonet Mount and Fixed Shell. However, some may be buried deep inside.

    • Even some simple electronic repairs like replacement of a blown driver transistor on the POW PCB.

      Level of difficulty: 3-5. In addition to access to the relevant PCB, some ability to test for basic component failures and skill in replacement of extremely small surface mount parts will likely be required. And identifying the part may prove challenging due to the SMT marking codes not being well documented.

    • Replacement of a bashed back lens group. *

      Level of difficulty: 2 but see * note.

    • Erratic behavior after long time in storage. *

      Level of difficulty: 0. Lenses that have been unused for a while but not in a sealed bag or container may experience buildup of a thin film of contamination on internal surfaces and contacts - specifically on the Focus and Zoom Encoder strips and switches. These lenses are not sealed at all. This may be particularly likely near or in a kitchen or machine shop but can happen almost anywhere. Working focus and zoom back and forth a dozen times may may be all that is required. If the lens will shoot at all, check the EXIF data on the resulting images to confirm at least that the zoom settings read back correctly. If this doesn't work, extensive disassembly may be required bumping the level of difficulty up significantly. Depending on the specific lens, one or both of these encoders may be buried deep inside, though sometimes access is provided by a window covered with a removable panel. For example, the AF-S DX 55-200mm f/1:4.0-5.6 VR lens has this for the Zoom Encoder (though not the Focus Encoder), accessible after the Rubber Grip is removed.

      The same applies to Focus A/M or VR ON/OFF switches that don't have any effect. For many lenses, a single screw releases the switch plate providing access to test the switches and use some contact cleaner sparingly if needed. But take care not to rip the flex cable.

    • Cleaning of the rubber grip. After a while these can get pretty ugly. ;(

      This is best done removed from the lens. It is generally possible to use something thin (but not sharp) to lift the front edge of the rubber grip and then go around and work it off the lens. Note that not all are symmetric so take note of front and back if that is the case. There is usually little or no adhesive securing it. Then it can be cleaned with soap and water and an old toothbrush. Dry thoroughly and replace. The only gotcha is that on some lenses, the rubber is so flabby that it won't return to its original shape and may be slightly loose. But sometimes it just takes time get back in shape. Otherwise, a bit or rubber cement may be used to secure it. And a replacement may be available.

    * On many lenses replacing some of the lens groups - including just putting the same ones back in place - in theory require optical alignment which is not possible without the proper Nikon test equipment and training. How well the lens would perform without alignment is not known. Even the thickness of any shims under the front lens group or Bayonet Mount are unique to each sample of the same model lens. The rear / back lens group is often mounted with oversize holes so it can be adjusted laterally before tightening the screws. If removing one of those, take a closeup photo first so it can be replaced as close as possible to its original position.

    Some parts like the Bayonet Mount may be available at reasonable cost from Amazon, eBay, or even Nikon (gasp!), but anything else is likely to have to be cannibalized from a similar lens and the cost will be ridiculous if purchased by themselves. So what's the point other than for the challenge or excitement value. ;-) If you do decide to take the plunge on a more involved repair, shoot closeup photos at every step even if there is a repair manual available. The on-line repair manuals tend to be written in Japanish :( ;-) with many assumptions that are not documented. How the parts go back together may seem obvious as it's being taken apart, but may not be obvious an hour or day - or even a minute later. Label parts that fit together with "match marks" of some sort like coded scratches or white paint. Many assemblies may appear to have 3-fold symmetry, but that doesn't mean they will work correctly if the wrong choice made. In some cases it isn't quite 120 degrees; in others there are subtle differences preventing engagement of various parts. In short, adding match marks during disassembly is essential to retaining sanity when putting it all back together. Where a repair manual exists, it may references specific features but this is hit or miss. Segregate screws as well since not all the teeny-tiny screws are identical and that may only become apparent under a strong magnifier. Work on a surface where tiny parts won't go bouncing off to oblivion. There are unique screws for plastic and metal, and of different diameters and lengths. A padded surface may be useful as well as a magnetic pad to "store" screws and such. Or an egg carton or pill orgnaizer. Many of the threaded holes are in soft plastic so stripping them is always a risk. If a screw seems tight, it's probably the wrong diameter or length. A set of quality Jeweler's or miniature precision Philips screw drivers with magnetic or magnetizable tips is a must.

    If a dozen of the identical model lenses need repair, then after the first 8 or so, this will become straightforward. ;-) But "identical" really means exactly the same model - the design of most of the half dozen 18-55mm lenses differs enough that becoming familiar with one doesn't help much much with any other if going deep inside. For example, even the AF-S 18-55mm VR and VR II lenses are not very similar with respect to disassembly and parts replacement since they are different design generations. Only the VR and non-VR versions of the AF-P 18-55mm may be close enough for government work but is not yet known for sure. This most likely applies to other lenses as well if going beyond removal of the parts at the back of the lens.

    These aren't like your great uncle's SLR lenses - and even those were basically impossible to repair without proper precision tools, most excellent eyesight and/or a microscope, and a steady hand. There are serious high tech parts in Auto Focus (autofocus or AF) Vibration Reduction (VR) zoom lenses including a miniature motor or motors, and possibly a gear train, angle encoders and other sensors for zoom and focus, MEMS gyros and voice coil actuators, PCBs with highly integrated ICs including a microcomputer, and many fragile flex-cables and connectors. In short these are complex intricate electro-mechanical systems, not just a bunch of optics! Though even the basic "kit" AF-S DX Nikkor 18-55mm f/3.5-5.6G VR zoom lens has 11 individual optical elements including one that is aspherical, and others like the Nikon AF-S DX 18-200mm f/3.5-5.6G ED VR II may have 16 or more.

    And while modern lenses in this class are amazing feats of mechanical design with sophisticated electronics, they do NOT have the look and feel of older "dumb" lenses with milled aluminum focus and aperture rings on well lubricated tracks. ;-) Rotating parts in these lenses are nearly all molded/formed plastic constructed with mostly sliding parts with minimal lubrication and a few rollers (but without frictionless bearings) in a few key places. There is no precision machine work to admire and forget silky smooth operation. Even on a brand new lens, this is obvious when rotating the Zoom Barrel. Having said that, they work remarkably well and provide features like autofocus and vibration reduction that one could only have dreamt about with older gear. I do not know whether high-end modern lenses are constructed any differently, but these are what most of us can afford. ;-) And even they typically have a cost if purchased new of several hundred to several thousand dollars.

    Where there is a Nikon repair and/or parts manual available on-line for the specific model lens, a set of search terms is provided to find it. Should they fail to return anything useful because of decayed links (which is unlikely), I mayy have a copy available for the asking. If there is no exact match, a repair manual for a slightly different model lens could prove useful even if the details are not same. But the "repair" manuals are really just disassembly and reassembly manuals with little to no diagnostic information, no explanations of principles of operation, and generally don't go down into the nitty-gritty where the real challenges are in putting things back together. Even the "parts" manuals do not break the lens down below the level of the core (where much of the optics and VR assembly is). They are partially in Japanese and make many assumptions about the user's level of expertise. And while theinfo on alignment - often required after replacing some parts or even just reinstalling them - is quite detailed, it assumes the use of Nikon proprietary jigs and software. But there are numerous diagrams and photos, though none provide the level of detail below with respect to AutoFocus (AF) and Vibration Reduction (VR) implementation. In fact, over half of the typical manual is devoted to the post-repair calibration.

    Most of the lenses discussed here have "Vibration Reduction" (VR) - a "Steadicam" of sorts inside the lens - which reduces the effects of camera shake especially for telephoto shots. Most popular lenses today have this feature. However, VR is not a cure-all for an unsteady hand. It can only do so much. If one comes to depend on VR and not pay attention to keeping the camera steady, the results can end up worse than without it.

    One would think that the non-VR lenses with the same name will be mechanically similar and thus the descriptions, etc. will also be similar sans references to the VR components. Apparently, this is not so. For example, comparing the repair manuals for the AF-S DX Nikkor 18-55mm f/3.5-5.6G VR and AF-S DX Nikkor ED 18-55/3.5-5.6G show them to differ significantly, possibly because the non-VR version is an older design. (The ED II version may be somewhat similar though.) Perhaps for lenses sold today, they would be similar. But manuals for those are not available on-line yet.

    Note 2: The names for the same lens may differ subtly in various locations in this document, and in the photos and Web Albums. In some instances this is because characters like "/" cannot be used in a filename. But most often it's that I was not consistent when originally assigning names and am too lazy to go back and correct the 75 places where they are screwed up. The differences are irrelevant and anyone with at least the intelligence of a carrot should be able to figure out to which lens they apply. Live with it. ;-)

    Nikon AF-S and AF-P Autofocus Lenses

    While there have been many types of Nikon lenses over the years starting with totally manual focus and versions of Auto-focus with the focus motor in the camera body, the two most relevant types now are designated AF-S and AF-P. AF-S uses the so-called "Silent Wave Motor" (SWM) which is not a normal electromagnetic motor but uses two phase high voltage ultrasonic signals to rotate a solid metal disk or ring. Most AF-S lenses then use a gear train to actually drive the focus mechanism. The (mostly) plastic gears do make some noise but it is usually not objectionable. A few AF-S lenses use a rotor the diameter of the focus ring with no gears so there is no gear train noise but it still not silent. The Nikon D1 introduced around 1999 is supposedly the first DSLR to support AF-S lenses. And AF-S lenses are compatible with all subsequent DSLR models to the present day (now 2026). Older DSLRs still have the internal focusing motor so they can work with older (pre-AF-S) lenses having autofocus capability.

    AF-P lenses use a miniature stepper motor with "P" supposedly standing for "Pulse", since pulses drive the two phases of its windings. Manual focus is also "fly-by-wire" in that the focus ring is linked to what is essentially a rotary encoder that sends pulses (two phases in quadrature) to the focus motor but is not mechanically connected to it. (Unfortunately, this means that if the electronic focus is inoperative for any reason, there is no manual focus backup.) AF-P lenses were introduced around 2016 but are NOT compatible with older Nikon DSLRs. They are partially compatible with some like the D5200 if the latest firmware is installed. Check the on-line Nikon compatibility chart for your camera(s) or just ask Google AI. Exactly why this incompatibility should exist is not known, as it would appear from a design standpoint to have been possible to make the AF-P lenses backward compatible.

    There are only 3 types of AF-P DX zoom lenses (and probably always will be only 3 since there is no effort going into new designs for F-mount gear): the AF-P DX 18-55mm f/1:3.3-5.6G "kit" lens (VR and non-VR versions), the AF-P DX 10-20mm f/1:4.5-5.6G VR wide angle lens, and the AF-P DX 70-300mm f/1:4.5-6.3G telephoto lens (VR and non-VR versions). There is also an AF-P FX 70-300mm f/4.5-5.6E ED VR full frame telephoto. Nikon Z-series lenses use similar stepper motor technology for focus but don't call it out explicitly.

    The AF-P DX lenses were all designed around the same time, probably by the same design team, so they share many similarities. These include the general construction of the front and back sections and the lack of any shims or spacers for fine tuning. The front Lens Cluster is 3-fold symmetric; the back one goes in only one way, though the mounting holes may be large enough that some small amount of lateral adjustment is possible for ultimate optical perfection. The FX version may be quite different as it has a metal Bayonet Mount and fully electronic aperture control with no physical lever (similar to that of Z lenses). Comments are pending the availability of a sample.

    Chart of all AF-P Lenses

                                        (1)                (2)        Year
            AF-P Lens Model            Optics    Focus   Aperture  Introduced
    --------------------------------------------------------------------------
     DX 10-20mm f/1:4.5-5.6G ED VR   ?C/11G/14E  Pulse  Mechanical    2017  
     DX 18-55mm f/1:3.5-5.6G ED      3C/9G/12E   Pulse  Mechanical    2016  
     DX 18-55mm f/1:3.5-5.6G ED VR   3C/9G/12E   Pulse  Mechanical    2016  
     DX 70-300mm f/1:4.5-6.3G ED     ?C/10G/14E  Pulse  Mechanical    2016  
     DX 70-300mm f/1:4.5-6.3G ED VR  ?C/10G/14E  Pulse  Mechanical    2016  
     FX 70-300mm f/1:4.5-5.6E ED VR  ?C/14G/18E  Pulse  Electronic    2017
    

    Nikon AF-P Nikkor VR Zoom Lenses is a comparison of the 4 versions set at minimum length - thus 18 for the 10-20mm and L for the 18-55mm. The non-VR DX 18-55mm and DX 70-300mm appear identical except for the lack of the gold "VR" on the label.

    1. E: Lens Elements; G: Lens Groups; C: Lens Clusters. Lens Elements are individual optics which may be glass, Extremely low Dispersion (ED) glass, or plastic, and may be normal (spherical) or aspheric. Lens Groups may be a single Lens Element or a glued combination like an achromat. Lens Clusters are my terminology for the sets of Lens Groups that move when changing the zoom setting. There will also be a focus group which will be part of one of the lens clusters and moves with respect to it. See the specific lens architecture diagrams in the lens dissection Web Albums for details. A Web search for the specific model lens may also turn up more on the optical design.

    2. Prior to the AF-P FX 70-300 mm, Nikon lenses are believed to have all used a mechanical linkage to operate the aperture blades via a lever from the camera body. This lens appears to be the first to use a stepper motor to operate the aperture (separate from focus), which is how Z lenses also do it (though the details differ, Z cameras and lenses were introduced a year or so later). This also means that it is not possible to manual inspect through a lens by opening up its aperture mechanically.

    Exactly why there is no non-VR version of the 10-20mm lens is a mystery, as that would seem to be the one to benefit the least from VR.

    Unfortunately, there do not appear to be any on-line repair manuals for AF-P lenses. The document dump that made repair manuals available for older lenses including most AF-Ss never took place for AF-Ps. Nikon has repair manuals of sorts on-line for some Z gear including lenses but not for AF-P lenses. "Of sorts" means they are along the same lines as the ones for the AF-S and other lenses, though some may have fancier color diagrams. ;-)

    As a side-note: The manufacturing cost of the focus mechanism in AF-P lenses must be only a fraction of that for AF-S lenses, perhaps be a factor of 10 or more as both the motor itself and the drive electronics are trivial in comparison. So while AF-Ps are cost-reduced, they are incompatible with older cameras. Go figure. ;-) But they should be more reliable. However, instances of total focus failure on AF-P DX 18-55mm lenses and partial or intermittent focus failure on others like the AF-P FX 70-300mm lens are not that uncommon.

    However, I have come across a few AF-P lenses in excellent cosemtic condition with no signs of trauma where Focus was totally dead. Swapping the PCB in one made no difference. A few others had no external signs of abuse but the focus mechanism deep inside the lens had been dislodged resulting in unpredictable focus lock and horribly messed up photos.

    Replacing the parts that get damaged the most is straightforward and low risk. For the back, it is just basically screwdriver work to replace the Rear Cover Plate, Camera Contacts and Housing, Bayonet Mount / Back Shell (which are one piece except for some unfathomable reason in the 10-20mm lens), PCB, and Rear Lens Cluster (with caveats with respect to alignment). For the front, it is simply peeling off the label and 3 screws each for the Filter Ring and 1st Lens Group. There are some details that can be annoying like getting the label back in place in an undetectable way and not losing that spring in the Grounding Contact Assembly. These procedures are virtually identical for all of the AF-P DX lenses, Details for the AF-P FX 70-300mm are not yet known.

    However, gaining access to anything beyond the 1st Lens Cluster in the front or PCB in the back can be challenging. While the focus mechanism should be reliable due to its simplicity (just a stepper motor and worm gear), it is buried deep inside the lens. This is unlike the SWM and gear train on AF-S lenses that is usually exposed once the Back Shell is removed, or even in some lenses by simply removing a switch plate cover.

    Nikon Lens Specialized Test Equipment

    These are DIY devices that could be potentially useful in dealing with common lens failures, though building them for one lens is probably not worth it.
    • Lens test rig: On some of these lenses, it is possible to remove the part at the back of the lens called the "Fixed Shell" (that has the labels and possibly focus A/M and/or VR switches) and replace everything that had to be taken off to get to it. This naked ;-) lens will then mount on a camera and operate normally but key components will be exposed for probing or replacement. One example of a lens that accommodates this stunt is the Nikkor AF-S DX 55-200mm f/1:4.0-5.6G VR. (See the section below which includes photos.) For this lens, the autofocus Silent Wave Motor (SWM), its driver "POW" PCB, the main "CPU" PCB, and various mechanical parts are easily accessed with the Fixed Shell removed. Wires can be attached to key signals like the SWM drive to make measurements in situ. CAUTION: While the steps needed to remove the Fixed Shell are similar for most of these lenses, without it in place, some are designed such the zoom ring can then be rotated past the normal stops. Then bad things can happen, like other parts of the lens falling out of their guide channels - then it can be tricky to put the thing back together. It is not even currently known if the other two versions of the 55-200mm f/1:4.0-5.6G lenses can be undressed in this way without risk. Also, on lenses with a manual focus ring adjacent to the Fixed Shell, it will no longer be held in position. And some lenses have the an encoder strip or contact assembly on the inside of the Fixed Shell, so not only will zoom and/or autofocus be messed up, but there is a risk of damaging the contact assembly. In short, your mileage may vary.

    • VR lens exerciser: For people with normal vision it may be obvious when VR is actually working: Look through the viewfinder or at the Live View image and press the shutter button part way. The jitteryness of the image should decline dramatically. For those of us for which this isn't obvious, some assistance may be desirable especially with lenses having modest maximum zoom.

      However, before embarking on a construction project, there are indirect ways of determining that VR is at least active. On older lenses like the AF-S DX 18-55mm f/1:3.5:5.6G VR there will be a distinct click when the shutter button is pressed and another a second or or so after it is released. This is the mechanism that locks the VR lens group first disengaging and then reengaging. On newer lenses like the AF-S DX 18-55mm f/1:3.5:5.6G VR II or AF-P DX 18-55mm f/1:3.5:5.6G VR there is no lock mechanism but a very faint click may still be audible. Associated with either may be a just noticeable jump in the viewfineder or live view image as the VR engages and disengages. However, a significant shift in the image is probably bad. And for all VR lenses, a faint buzz or white noise will be audible with ones' ear pressed against the barrel of the lens after focus lock but before VR turns off. This is the VR servo doing its thing. These don't prove VR is actually working correctly but are a good indication that it is not dead. Of course check the position of the VR ON/OFF switch if any, move it back and forth a dozen times. If That doesn't do anything or if it is intermittent after excercise, clean it using an environmentally-friendly solvent by removing the switch plate if possible (typically one tiny screw) taking care not to stress the flex cable. If it's part of the Fixed Shell, it will be necessary to go inside. Do NOT just spray from the outside or dunk the lens in solvent. Some cameras may have a VR enable option in one of the menus. But VR works on other similar lenses, the problem is in the lens.

      And on one lens, something inside made a loud grinding noise when the camera or VR switch was turned on as though VR was attempting to initialize but perhaps getting bogus data back from a gyro. VR did not work on that lens. ;(

      Having said that, the VR lens exerciser is a simpler version of what Nikon uses to test and adjust VR lenses, It consists of a platform mounted on springs or rubber feet for the camera with lens and some means of introducing controlled pan and tilt vibration over a range of frequencies - perhaps a small motor with an off-center weight or a voice coil driver. A remote shutter button would enable the shutter to be half depressed without adding vibration of its own.

      The prototype consists of an aluminum plate with soft rubber grommets near the corners to act as compliant feet and several 1/4 inch holes with which a camera can be attached to more or less put the platform's center of gravity in the center depending on the attached lens. A small DC hobby motor with an off-center weight generates the vibration. It can be mounted at various locations and orientations and these will determine how the rig moves. Which one is best is still being investigated. See Nikon Lens Vibration Reduction Tester. The location shown creates circular motion exercising VR in X and Y.

      The platform wobbles nicely - too nicely as the amplitude can easily exceed the capabilities of the VR system. ;-) And it's almost impossible to determine anything definitive through the viewfinder or using Live View on the camera's LCD: Everything shakes which obscures the effect of vibration reduction. While it's possible to connect to a PC via USB, the update rate may not be adequate. So, an external monitor is required and this works quite well using either the A/V or HDMI output on those cameras that have Live View with real time video. The effect of VR is very obvious and the limits of its capabilities can be easily explored by adjusting the amplitude of the wobble. See AF-S DX 18 200mm f3.5-5.6G VRII VR Test1. This starts with the VR switch OFF and then approximately half way through it is turned ON. See the typical photos in Vibration Reduction Effectiveness for Long Exposure - Off and On Comparison 1. Since the amplitude of the vibration for these tests is near the limit of what VR can handle, the result is not perfect. But the improvement is still dramatic. And I figured that using an antique camera as the subject would be fitting. ;-)

      What is strange though is that the behavior of VR on two different cameras (D5200 and D5600) and with multiple lenses does not agree with either the user manuals or the comments on various Web forums: For several lenses tested, the VR state is determined solely by the setting of the VR switch on the lens. Pressing the shutter button makes no difference and the expected "click" indicating that VR is being locked or unlocked occurs only when moving the switch on the lens back and forth. However, the D5200 has known issues with respect to the shutter button so this may be related. But on the D5600 which has a menu setting to turn VR on and off, the OFF option is grayed out for the AF-S DX 18-200mm f/1:3.5-5.6G VR II lens. I have read that some experienced photographers prefer VR to be off under certain conditions including when shooting on a tripod. Perhaps they are concerned about electrical noise causing random movement of the VR mechanism fuzzing up the photos even when VR shouldn't be doing anything. So the switch on the lens must be set to OFF.

      Nikon Lens Vibration Reduction Tester 2 shows the complete setup which uses a D5200 with an ancient (pre-digital and otherwise mostly useless) LCD TV to display the real-time NTSC output. While there are many mini-LCD displays available with both A/V (RCA) and HDMI inputs, I have not found an inexpensive one that supports the ~4:3 aspect ratio of the camera's output. So the oldie but goodie here is being used for a noble purpose. ;-) The lens being tested is an AF-S DX 18-200mm f/1:3.5-5.6G VR II. The wired shutter release was thought to be useful to avoid vibration but for some reason, it won't engage autofocus. Perhaps it doesn't have the half-depressed contact or that is the bad connection in this D5200. A wireless remote shutter release (IR for the D5200) does and the AE-L/AF-L button on the back of the camera will as well. The gizmo with the knob is a digitally adjustable DC-DC driver for the motor. The off-center weight can be seen to be spinning and indistinct in this several second exposure, yet the real-time display of the antique Nikkormat is fairly sharp. Nikon Lens Vibration Reduction Tester 3 shows the same setup with a Nikon AF-P FX 70-300mm f/1:3.5-5.6E ED VR lens aimed at a lens test chart. As the amplitude of the vibration (power to the motor and thus its speed of ratation) is increased, there will be only a very minimal change in the jitter on the display until the point where VR lock is lost - and that will be obvious.

      All VR lenses including those destined for resale spend time on this rig. It should also be possible to mount a Nikon Z camera on the platform and test Z lenses as well as the In Body Image Stabilization (IBIS) in a similar manner.

    • AF-S Silent Wave Motor (SWM) tester: This provides 2 phases in quadrature of a variable frequency high voltage drive to exercise SWM and Ultrasonic Pieso Ring Motors. It consists of a 555 timer feeding a 2 bit shift register to provide phase A and B signals with a frequency range of <20 kHz to >300 kHz, H-Bridge transformer driver, and a pair of ferrite step-up transformers. In principle, the POW PCB from a defunct AF-S lens could be used for part of this but that could be challenging without documentation. An alternative to the 555 timer is an Arduino with suitable firmware to both generate the required waveforms and provide a readout of frequency, voltage, etc. ;-) But that isn't going to happen. ;-)

      Prototype #1 uses a 555 timer for the master clock, a two bit shift register to generate the two phases in quadrature with a reversing switch, and a discrete totem-pole driver and ferrite transformer with a 1:10 turn-ratio for each phase dug up from the depths of a junk box. See the circuit at Sam's Nikon AF-S Lens SWM Tester 1 Schematic. The TTL phase generator was built on a prototyping board with the HV drivers on a solderless breadboard as shown at Sam's Nikon AF-S Lens SWM Tester 1 Prototype V1. The phase generator is at the upper left with the high voltage driver below it. The POW PCB from an AF-S DX f/1:3.5-5.6G VR zoom lens can be seen at the upper right. ;-) The extra space on the prototyping board is for the final driver circuit if that ever happens. In the meantime, the stuff on the solderless breadboard was moved to a smaller phototyping board and bolted to the large one as shown in Sam's Nikon AF-S Lens SWM Tester 1 Prototype V2 and Tyical Waveform. The shape of the waveform is quite similar to that of the Nikon driver. And yes, if one looks carefully, the physical driver circuits are not quite 100% identical to the schematic. ;-)

      But think of this as a "simple" generic circuit and not something to copy directly since it is marginal in the voltage department, assumes the use of transformers that one can't buy at Digikey, and the transistors should probably be replaced with higher power devices as they do get hot especially toward the upper range of the test conditions. But V3 below would be worth considering though the transformer would still need to be custom wound.

      Having said that, the frequency range is from 15 kHz to 300 kHz and the maximum output voltage is above 200 V p-p up to around 70 kHz and decreases above that. So this would probably not work for the SWM in lenses requiring a higher driver frequency unless their voltage requirement is much lower. And 200 V p-p is well below what has been measured for a sample lens (AF-S DX 55-200mm f/1:4.0-5.6G VR, see the info on the "Lens Test Rig", above) of ~240 V p-p. But even 150 V p-p is more than adequate to drive the SWM used for these tests (at low speed at least) if set close to the optimal frequency. For the test SWM from an AF-S DX 18-55mm f/1:3.5-5.6G VR "kit" lens, this turned out to be 73 kHz. Even as low as 100 V p-p more or less worked when the SWM was in a good mood. It's a minor miracle that these transformers even came close to being useful as they are left over from some sort of SMPS project (not even my own). And they are only about 125 times the volume of the transformers in the actual lens. ;-) An attempt was made to add turns to the secondaries to see if the voltage could be boosted, but that did not result in any uesful improvement and actually made things worse, eventually blowing the drive transistors when pushed too hard. This is complicated by the fact that the SWM is a largely capacitive load, measured at 1.3 nF for the one in the AF-S DX 18-55mm f/1:3.5-5.6G VR lens. The capacitance kills the output and shorts the input to the typical ferrite transformer designed for use in inverter-based HeNe laser power supplies. To get higher voltage from the same circuit would probably need both better driver transistors and more copper (primary and secondary turns) in the transformers as they are saturating at the upper limit of the input voltage range. But the waveforms this circuit generates are remarkably similar to those shown in Example Nikkor AF-S SWM Drive Waveforms for Phases A and B. (In the interest of full disclosure, the blue trace was measured but the yellow one was just copied as the naked lens had only a single working phase.)

      A slightly simplified version was also prototyped. See Sam's Nikon AF-S Lens SWM Tester 2 Schematic. However, its performance is similar. But never fear, help is on the way. ;-)

      What never ceases to amaze me is that the tiny PCB, with dimensions of 1-1/4x3/4 inch and its 3/8th inch square ferrite components running off 5 V or less can drive the SWM at full speed without working up a sweat! And ohmmeter tests suggest that they do use simple transformers to generate the high voltage output. There are only two pairs of connections to them with resistances of around 0.1 and 12 ohms, respectively and they do not share any connections. One end of the output goes to the SWM; the other goes the center pin of an SO3 part with another lead going to GND. So it may not be magic after all. Also, photos of the PCB from an AF-S 24-70mm lens show E-E core magnetics with exposed windings that look like transformers. ;-)

      Further, a patent search for "Nikon Silent Wave Motor" turns up in at least a half dozen with the following circuit: Driver Schematic for SWM from Nikon Patent. And this bears a remarkable resemblance to what is actually present in every AF-S lens model I've dissected, though the transformer turns ratio may be greater than 50:1 and not 1:1. Confirming that will be a PITA due to their small size.

      Looking at the circuit closely, it would appear to be somewhat similar to a flyback driver. When the input phase is positive turning on the primary-side MOSFET, current builds up in the primary but secondary current is blocked because its MOSFET is off. When the input phase goes negative, current ceases in the primary, the magnetic field collapses and transfers its energy to the secondary which has its MOSFET turned on, so the current flows out to the SWM electrode (capacitor). The output voltage gets a boost both from this burst of current and the turns-ratio. I'm still stuck with the same transformers but found one where the core can be separated so a spacer can be added to increase the leakage inductance if necessary, as in a real flyback converter.

      (An alternative that also shows up in an early Nikon patent (US5179311) is what may be described as a "resonant charge pump". But that requires the two coils to be joined and other parts that don't appear to be present on the POW PCB.)

      A funny thing happened on the way to prototyping the quasi-flyback topology. See Sam's Nikon AF-S Lens SWM Tester 3 Schematic. With only the primary-side driver and adjustment of the core gap, the output almost doubled compared to V1 and V2. So with 15 VDC input, the output is 240 V p-p and at 20 VDC input, it is over 300 V p-p, both using the 1.3 nF simulated SWM load. This is roughly 16 times the DC input voltage. And this circuit is so dirt simple. The 2N5551 is a high voltage (160 V) bipolar transistor needed because when it shuts off, more than double Vss appears across its C-E. But if Vss is limited to 15 VDC, a 2N3904 would probably be just fine. The 2N5551 doesn't even get warm. The purpose of the capacitor and diode in the base circuit are to prevent the transistor from shorting the power supply if the input signal get stuck high. A current limiting circuit using an LM340 could also be added for overall protection. The transformer core gap is somewhat critical for maximum output. However, it appears as though Murphy was on vacation so pieces of 1.6 mm (1/16") PCB material turned out to be near optimal to generate the maximum p-p output for a given Vss at the 69 kHz drive frequency. But the core gap is probably at least somewhat sensitive to frequency as well as load. AND the waveform looks even more like that of the Nikon driver! ;-)

      However, I did not anticipate the following when constructing the dual phase driver on a single board:

      1. There is a huge amount of coupling between the transformers in close proximity largely due to the fringe fields from the gaps on the sides of the "E-E" cores. So tuning one phase for optimum performance (shape and amplitude) caused the other one to change from the nice waveform in the photos to a sinusoid of much lower amplitude. AND there is hysteresis such that the nice and ugly would flip back and forth depending on the core gap and even input voltage, without any region where both look decent. In fact there is so much coupling when the transformers are oriented so a pair of gaps is in close proximity that if the drive to one of the transistors is removed, its transformer's will still produce a substantial output voltage.

      2. This is really a system where resonance provides much of the increase in amplitude. Thus even though the A and B digital signals are always ±90 degrees with respect to each-other, the resulting phase shift of the A and B outputs depends critically on the core gaps. Usually it's within a usable range but would probably not track if the input frequency or phase shift were changed.

         Sam's Nikon AF-S Lens SWM Tester 3 Output Phase and Shape versus Drive Frequency is an animated GIF showing what happens over a relatively narrow range of frequencies below and above the optimal 69 kHz. No, I'm not doing an actual video! ;-) Below 69 kHz, the shape "snaps" between the top two scope traces as the frequency is changed; Above 69 kHz, the transition is gradual but there is an unstable region as shown where it oscillates between them. Over the full ~9 kHz range, the relation between the drive and output phase changes by at least 90 degrees. Within the range where the shape has the double lump, the output voltage is near maximum and relatively constant, but declines on either side. These tests were done with a single driver without a second transformer in the vicinity so there are no coupling effects.

      (1) can be dealt with most easily by separating the transformers and mounting them so their fringe fields are at right angles to each-other (or perhaps with a shield). (2) requires careful tuning of the core gaps. Both of these can be achieved at the same time but it is a bit annoying. However, coupling could be reduced to manageable levels by simply rotating one of the transformers by 90 degrees to separate the core gaps. The exciting exploration of all this is left as an exercise for the bored student. But with care, at least 300 V p-p is possible before one or both waveforms gets corrupted. However, to achieve that p-p output voltage, the input voltage must be increased from 0, not switched on suddenly, and if the thing switches to weird mode, the input voltage will probably need to be reduced to 0 V to recover. Got that? ;-)

      Given that this is only for testing and would never fit inside a lens anyhow, there is little point in adding the secondary-side components and thus there isn't likely to be a V4. ;-) For anyone handy at winding simple transformers, V3 would be recommended even with the fiddly adjustments. The only additional construction that was undertaken is a single copy of the boost circuit just to have something more "compact" to demonstrate without strange behavior using an external clock and scope. ;-)

    • AF-P Pulse (stepper) motor tester: Similar to above but for AF-P lenses. This is probably an unnecessary extravagance though as stepper motors really don't go bad much. But for someone who wishes to have every testing gadget, this could easily be implemented entirely with an Arduino since logic level voltages should be sufficient to drive the micro-steppers in AF-P lenses. Of course, it would need access to the stepper motor terminals deep inside the lens!

      A much simpler way to possibly determine something about AF-P functionality is with a sense coil similar to the one for checking SWM drive. Monitoring for electromagnetic emissions from the lens with a dozen turn coil seems to show when the stepper pulses are generated but the optimal location varies by lens model. There will be nothing from an AF-P lens with dead Focus, or where Focus has reached its limits. However, what is not known is if the stepper motor needs to actually be rotating for these pulses to be of decent amplitude. And they aren't exactly clean pulses under any conditions!

    Nikon Lens Replacement Parts

    Should it be determined that a specific part is defective and that it is likely to be within your experience/skill level to replace it, where to find a replacement? With a very few exceptions, Nikon will not be useful except for "peripherals" like caps and hoods. (And perfectly satisfactory non-Nikon versions are for these are available at a fraction of the genuine ones.) eBay and Amazon have numerous listings for lens parts, but these must be taken with a grain of optical sand ;-) as the sellers often have no clue about the differences among lenses. (This also applies to sellers of the lenses themselves!) So the listing photos must be carefully examined to determine if they even apply. A large percentage will be for a totally different lens and will not be compatible. And forget about the main PCB with the CPU and memory if your lens isn't recognized by any camera. They may have parameters in NVRAM optimized for the specific lens. Searching on eBay for "nikon 18-55mm vr ii lens (motor,parts,pcb)" (or whatever the specific lens is) should turn up sample listings. Amazon searches may need to be more specific as their search engine is brain-dead from a practical point of view (though perhaps not for maximizing their profits). The ridiculous prices the sellers are charging for most replacement parts can be quite amazing (and amusing). ;-) In fact, given the relatively low cost of used or "parts" lenses, it almost never makes sense to buy individual parts.Two exceptions may include the cheesy plastic bayonet mount plate and possibly the front lens group (cluster), which may be reasonably priced and easy to replace. The cost of other parts may exceed that of an entire working replacement lens. But if VR isn't working in a VR lens, it is unlikely the VR Assembly can be installed by mere mortals even if it is the correct type. That requires nearly total disassembling the lens. (The on-line repair manuals don't even go that deep.) And the problem may not even be in the VR Assembly. Furthermore, specialized Nikon test equipment and proprietary software are required to calibrate the lens after repair with parameters stored in NVRAM. And if VR isn't working, perhaps it's because the lens you bought is not actually a VR lens and the seller had no clue. ;( ;-) That is very common.

    Back Disassembly Steps Common to most Nikon AF-S DX Lenses

    While Nikon lenses vary is size and shape, access to the interior of the back of the lens is usually pretty much the same for all models, at least all those that are dealt with in this document. There may be slight variations these should get you started.

    CAUTION: If these steps are not performed in the exact order shown, the Camera Contact flex cable may be torn rendering the lens useless.

    1. Remove two screws securing the Camera Contact strip.

    2. Remove three screws securing the Inner Ring to the Bayonet Mount.

    3. Set zoom so the rear lens cluster is retracted into the body of the lens.

    4. Remove the Inner Ring.

    5. CAREFULLY move the Camera Contact assembly toward the center of the lens so it slips into the hole.

    6. Remove the screws securing the Bayonet Mount. Small lenses have three but larger ones may have 4 or possibly more.

    7. Carefully lift the Bayonet mount off the back of the lens.

    8. On at least one lens (the 55-200 VR), the Aperture Tang does not come away freely but has a slot that is trapped by a peg on the aperture lever. For this, if the zoom is adjusted so the back lens cluster is as far inside the lens as possibly, the Aperture Lever may be pushed toward the center allowing the Aperture Tang to come free. On all the others it simply slips in place.

    9. Note the number, orientation, and stacking of the shims. There will be anywhere from 1 to 5 or more. Photos and a Sharpie™ will come in handy. ;-)

    10. If there is a switch panel on the lens, remove its screw so that it can then be slipped though its hole when the Back Shell is removed. On newer lenses the cable from the switch panel unplugs and it can just be removed entirely; on older ones it may be there may be discrete wires soldered to one of the PCBs.

    11. All lenses have a grounding wire between a spring contact assembly which must be disconnected. It usually goes between the Bayonet Mount and a solder pad on one of the PCBs or a flex cable. This may be accessible through the switch panel cutout. Protect the plastic with Kapton tape or something else to prevent accidental damage from contact with the soldering iron. It can also be unsoldered at the Bayonet Mount end though putting it back becomes more fiddly. Also, DO NOT be tempted to unscrew the spring contact assembly rather than unsoldering the wire as putting that back is even more fiddly and the wire will probably break off anyhow. ;( ;-)

    12. It should now be possible remove the Back Shell.

        CAUTION: On some lenses, the zoom range is restricted by the presence of the back shell. Bad things can potentially happen if zoom is changed and it goes beyond the lower or upper limit. Namely parts of the lens will fall to bits making reassembly trickier. ;-(

    Lens Spacers and Shims

    Even if a lens design is perfect, there may be some variation in the focal length and symmetry of the optics, and machining and molding tolerances of structural parts. The primary means of accommodating for these is by the use of spacers and shims between the Lens Clusters and Bayonet Mount and what they seat against.

    Spacers may be present on most or all AF-S lenses; shims behind the front lens cluster mount on larger ones. AF-P lenses may not have either.

    • Spacers: are rings of uniform thickness made of metal (often stainless steel, copper, or brass) or plastic, and there may be a dozen or more different possible thicknesses used alone or in combination. For example, the thickness for the AF-S DX 18-300mm f/3.5-5.6G ED VR Zoom Lens, the spacer(s) between the Bayonet Mount and body of the lens range from 0.05 to 0.5 mm in thickness; for the focus lens cluster they range from 0.03 mm to 0.5 mm, and for the 1st Lens Cluster the range is 0.05 to 0.4 mm. Two or more of these spacers may be used in any given location to make up the required total thickness. One or more spacers are present with most lenses.

    • Shims: are a portion of a ring or smaller section used to compensate for an asymmetry most often associated with the 1st Lens Cluster for larger zoom lenses. (They are rarely present with the 18-55mm "kit" lenses.) For the same 18-300mm lens as above, there may be three of these located 120 degrees apart and possibly all of different thicknesses ranging from 0.1 to 0.2 mm. Other samples of this lens, or other lenses may have only one or two. There may also be spacers in addition to the shims as noted above. The shims may be pegged to fixed locations or just "floating" with friction keeping them in place once the relevant lens cluster is secured.

    When removing the Bayonet Mount or a Lens Cluster, take note of the spacers that may be present and their order. Label them with a Sharpie™ as to back and front, and the relation to the index mark on the lens so they can be replaced in the same order and orientation. This will save on a lot of head scratching. The order may not be critical but it doesn't hurt to make an effort to replace them the way they were originally. The exception may be for the Bayonet Mount where a plastic ring if present (being an insulator) probably should probably face the inside of the lens.

    Shims are more critical since there may be two or three different total thicknesses made up of a combination of multiple individual shims. Even with only three shims of differing thicknesses, there are six permutations. Without the sophisticated lens test equipment Nikon uses, replacing shims that fell out in the correct locations could be quite challenging or at least time consuming. How much the correction for asymmetry matters in the end is not really known given the large free-play present with these lenses.

    Note that even though the thickness of the spacers and shims may seem to be insignificant, they directly affect the range of focus and the calibration of focus with respect to the readout via the markings on the lens and the EXIF data. For example, if the 1st Lens Cluster or Bayonet Mount spacers or shims are not installed, the closeest distance at which the lens is able to focus will increase and the distance displayed will bear no relation to reality. If there is too much thickness, focus at infinity may not be possible.

    My suggestion since you are probably reading this after all the shims fell out of your lens is to not worry so much about the asymmetry, but simply replace them so the thickness is correct, which probably simply means equal numbers of the same type shim (silver, copper, brass, etc.) all around.

    In principle, a test setup with a camera in Live Mode aimed at a test chart feeding a video display could be used to fine tune the shim thicknesses. For the 1st Lens Cluster, this would be straightforward on lenses where it could be loosened slightly but not removed so that test shims could be inserted behind it. However, there would still be challenges depending on the video quality as the focus error for miniscule tilt will be down in the weeds. It may require making test shots with the aperture wide open and displaying them at full resolution. And your mileage may vary. ;-)

    There is more on spacers and shims in the sections for specific lenses.

    Nikon F Lens Pin Assignments

    This is from Thom Hogan Nikon Lens Contacts SCRIBD. Pin assignments looking at the back of the lens clockwise from right to left:

      Pin   Function
     -----------------------------------------------------------------------
       1    Vcc (Power)
       2    RW or H/S (Read/Write, becomes RW1 if teleconverter is used)
       3    LCLK (Serial Clock, becomes LCLK1 if teleconverter is used)
       4    LIO (Serial data, becomes LIO1 if teleconverter is used)
       5    RW2 (Teleconverter use)
       6    LBAT (AF-S use)
       7    PGND (Ground)
    

    There is some more information via the link above but not a lot. And this does not cover the extension to the 8 contact F-mount (AF-P) lenses, or Z lenses. If you have more information on the F-Mount power and communications or anything on the Z-Mount interface please contact me via the Sci.Electronics.Repair FAQ Email Links Page.

    Comparison of Nikon AF DX 18-55mm "Kit" Zoom Lenses

    No, these aren't assembled using step-by-step instructions like Heathkits™. ;-) That would be quite a challenge. The term "Kit" applies to lenses bundled with entry to mid-level DSLRs (though also sold separately), specifically AF-S or AF-P DX 18-55 mm zoom lenses. DX refers to the sensor size of ~0.6x1.0 inches, around 2/3rds of the dimensions of the full frame (FX) format of more expensive DSLRs and antique 35 mm film cameras. The zoom range of DX 18-55 mm goes from modest wide angle to modest telephoto - equivalent to approximately 27-83 mm for the FX format. If you're old enough to recall the days when zoom lenses were a high priced luxury, a fixed 50 mm was the "Standard" lens, in the middle of the effective range of the 18-55 mm zoom lenses. For the casual photographer (who still wants to deal with a DSLR at all!), one of these lenses is probably all that is needed. (Or two, one as a backup if one is dropped!) They are relatively compact, light weight, have similar and very acceptable optical performance, and cover most shooting situations without fuss. They all autofocus quickly, quietly, and reliably. Most have "Vibration Reduction" (VR), essentially a "Steadicam" of sorts built into the lens, which is definitely worthwhile, especially at the telephoto end of the zoom range. Although list prices may be in the $300 range, in 2022, any of the lenses covered in the sections below can be purchased used on eBay guaranteed working and in decent cosmetic condition for under $60 delivered, and with luck and patience for under $35. Although versions may be available without VR, it makes little sense to bother with them as the cost won't be much lower, if at all - and due to the whims of sellers or of auction fever, could be higher. Of the three with VR, the AF-P VR lens is probably the most reliable and easiest to repair (or at least easiest to reassemble - pending me being successful, which should be coming soon). However, it will not work with older DSLRs. The runner-up would be the AF-S VR II (which I like based on its look and feel). The reliability of the AF-S VR and VR II is probably similar, but the not-II VR version may be the most finicky to repair despite there being an on-line "repair manual" for it. They all take good pictures, though the AF-S ED may be a bit lower in this respect due to its simpler optical architecture (fewer lens elements) but that isn't really known. It may be that the lack of VR allows it to be simpler without sacrificing optical performance. The Web is dripping with reviews comparing all of these and what's here is not intended to compete with them. ;-)

    Here is an implementation summary of known DX 18-55mm f/3.5-5.6G zoom lenses. There may be others:

                Gener-   (1)     Auto-   Focus     Focus       Manual       Year
       Model    ation   Optics   Focus  Encoder  Tachometer    Focus     Introduced
    --------------------------------------------------------------------------------
     AF-S ED      1   2C/5G/7E    SWM     Yes     Magnetic   Mechanical   2005
     AF-S ED II  1.5  2C/5G/7E    SWM     Yes     Optical    Mechanical   2007? (2)
     AF-S VR      2   3C/8G/11E   SWM     Yes     Optical    Mechanical   2007
     AF-S VR II   3   3C/8G/11E   SwM     Yes     Magnetic   Mechanical   2014
     AF-P         4   3C/9G/12E  Pulse    No        None     Electronic   2016  (3)
     AF-P VR      4   3C/9G/12E  Pulse    No        None     Electronic   2016  (3)
    

    Notes:

    1. E: Lens Elements; G: Lens Groups; C: Lens Clusters. Lens Elements are individual optics which may be glass, Extremely low Dispersion (ED) glass, or plastic, and may be normal (spherical) or aspheric. Lens Groups may be a single Lens Element or a glued combination like an achromat. Lens Clusters are my terminology for the sets of Lens Groups that move when changing the zoom setting. There will also be a focus group which will be part of one of the lens clusters and moves with respect to it. See the specific lens architecture diagrams in the lens dissection Web Albums for details. A Web search for the specific model lens may also turn up more on the optical design.

    2. Based on appearance, the AF-S ED II lens is believed to be most similar to the AF-S VR physically, but uses the ED optical design.

    3. Since the pulse / stepper motor for autofocus is inherently digitally precise, no encoder or tachometer is needed. It's not primarily to reduce cost. ;-)

    4. If considering buying one of these on eBay or elsewhere, carefully compare the title/description to the actual photos. With 6 models to choose from, the sellers often get it wrong. The simplest place on the lens to check is the label on the front.

    BTW, that "G" after the f-stop(s) in most Nikon later model AF-S and AF-P lenses stands for "gelded" which in essense means the aperture ring has been removed. However, the common definition of gelded may be slightly raunchy or obscene but does capture the flavor of its meaning for lens design. ;-)

    The AF-S ED is probably the original AF-S 18-55mm zoom lens. The ED II may be more similar to the AF-S VR without VR than the ED. The non-VR version of the AF-P 18-55mm lens is identical in appearance to the VR version except for the labels and based on a Nikon brochure appears to have the same optics as the VR version.

    A montage showing stock photos of all known versions of the 18-55mm kit lenses as of 2022 may be seen at: Nikon AF DX 18-55mm f/3.5-5.6 "Kit" Zoom Lenses. These are from Nikon lens product or review pages (copyright © Nikon Corporation) scaled so the relative sizes are close to correct. Photos of actual specimens coming soon.

    Note that the AF-S ED, ED II, and VR lenses have a filter mount that rotates with focus. This can be a pain if desiring to use a linear polarizer to enhance contrast or even an asymmetric lens hood since its orientation should remain fixed. What were they thinking? ;( It is fixed on the AF-S VR II and AF-P lenses.

    Diagrams showing the physical appearance and optical architecture of the 3 VR lenses may be found at: Comparison of Nikon DX 18-55mm 1:3.5-5.6G VR "Kit" Zoom Lenses.

    AF-S DX 18-55mm VR Zoom Lens Zoom Control:

    The following applies specifically to the AF-S DX 18 55mm VR Zoom Lens but others are generally similar. Although the design of the mechanism that moves the internal parts of the lens when zoom is changed may seem daunting, it is really quite straightforward. But putting the pieces back together can be a challenge.

    • The main structure of the lens that attaches to the camera bayonet mount has a set of 3 tracks / slots running along the axis of the lens that are not quite 120 degrees apart to break the symmetry and prevent parts from being installed rotated by 120 or 240 degrees.

    • A sleeve or barrel linked to the zoom ring or barrel has precisely designed slots cut or molded into it - one set of 3 for each lens cluster. These are what actually "program" the motion of the lens groups based on zoom position. Like the straight slots, they are also at approximately but not precisely 120 degree orientations to break the symmetry.

    • In the case of this lens, there are 3 such sets of slots, one for the Front Lens Cluster (Lens Groups 1-2), one for the Middle Lens Cluster (Lens Group 6), and one for the Back Lens Cluster (Lens Groups 4,5,7,8). These can be seen in AF-S DX 18-55mm VR Zoom Lens Zoom Sleeve. Rotating the Zoom Sleeve causes the 3 Lens Clusters to move axially over differing distances.

    • For the ED and ED II versions, there are only 2 Lens Clusters and thus 2 sets of slots; for the AF-S DX 18-200mm lenses there are 4.

    • For the AF-S VR lens, the slots are milled into an aluminum sleeve; for the AF-S VR II and AF-P lenses, they are molded into a plastic barrel.

    • Rollers of sorts fit fairly precisely into the slots so there is very little free play. However, as seen with at least one of the repairs, they can break. ;-( Nor are the rollers on any sort of frictionless bearings - they are just plastic on plastic or plastic on metal. For the AF-S VR II and AF-P VR, they are simply pegs that don't rotate.

    • Perhaps the biggest challenge in reassembling these lenses is getting all the zoom parts to line up correctly as they are inserted into the slots of the sleeve or barrel. ;-)

    Another challenge has been locating truly broken specimens of these lenses that I'm willing to use for dissection. Lenses listed on eBay as "For Parts or Not Working", "Untested", or even "Manual Focus Only" have turned out to be fully functional or easily repaired without going deep inside. In some cases it's because the lenses are not compatible an older camera the seller used for testing and so appear not to work. For others it's simply because the seller had no camera body to use for testing and they didn't want to risk a return. But overall, the reputation for poor reliability of AF-S lenses appears to be exaggerated. In fact I've yet to acquire an intact sample of a "Parts" AF-S where the SWM (Silent Wave Motor) or driver electroncs were faulty.

    More to come.

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED Zoom Lens

    There is a repair manual on-line for this lens. Search for "Nikon AF-S DX Nikkor 18-55mm f3.5-5.6 ED Lens Service Manual" (without the quotes). It's the second hit using Google. This manual may be slightly more detailed than the later ones, though some of the steps need more context to make sense. ;(

    The ED may be the first of the AF-S DX 18-55mm zoom lenses and not much is known about it other than what is in the repair manual showing significant differences compared to even the ED II version. That version appears to be closer to the AF-S VR lens, below.

    The AF-S DX ED has fewer lens elements, uses a magnetic instead of an optical tachometer for autofocus, and the construction is more complex and somewhat clunkier.

    I acquired one but since it is in good condition post cosmetically and functionally, it will be for external inspection only, not for dissection. There are no current plans to investigate this lens in greater detail unless someone would like to donate a sacrificial specimen for analysis. The asking prices on eBay are above may curiosity quotient for a lens to take apart and likely never put back together so it functions. ;-) Appropriate chants and incantations will be issued to the gods of dead camera lenses upon request but it will not likely survive the experience. :( ;-)

    See the Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED Zoom Lens Dissection Web Album. There is no dissection yet but it shows some stock photos, the optical architecture, how the lens groups move with zoom, an engineering diagram of the lens derived from one in the repair manual, and photos of the exterior in various poses. Most of these photos were taken with either a Nikkor 18-55mm ED II lens or the repaired 18-55mm ED lens - ID #2.

    Here is a summary of the Nikkor 18-55mm AF-S DX f/3.5-5.6G ED lenses I've acquired so far:

    • ID #1 (SN: US2834999): Fully functional...

    • ID #2 (SN: US2053837): Loose wobbly noisy Filter Ring resulting in erratic zoom and inability to focus. The cause was broken tabs causing the Focus Fork to not lock in place. Filter Ring only held in place by Trim Ring. Repair below.

    • ID #3 (SN: US2424548): Rear guide tube shroud / light shield loose inside lens visible in eBay listing photo. This lens is in absolutely mint external physical condition - perfect like new. But the innards are all twisted. ;( After removing the back parts (Inner Ring, Bayonet Mount, Camera Contact Strip), it was obvious this lens had been subject to extreme trauma. That loose part is a flare shield that moves up and back independent of the lens groups. But it has no optics, just a big hole. There was major obvious damage to the straight metal tangs that operate the zoom and aperture. All were bent and had even popped out of the slots they are supposedd to engage, almost certainly from excessive torque being used to attempt to change the zoom setting. Once these were straightened and reinstalled, it became obvious that this wasn't the tangs' fault. There is something seriously wrong with the spiral tracks on which the front and back lens clusters move. But exactly what it is is not at all clear. They look perfect. While they move freely by hand, they are almost impossible to move via the tangs when rotating the Zoom Barrel and would definitely become twisted again even. though they are quite beefy. In addition, the lever on the aperture assembly that operates the iris diaphragm itself got scrunched (technical term!) and in straightening it, a piece broke off. But that doesn't appear to be essential but may be there just to prevent the aperture tang from going in the wrong slot so no effort will be made to reconstruct it. With everything straightened, when installed in the only orientation that makes sense, the lens group/aperture assembly would fall out into the space between the Filter Ring and the front of the zoom spiral tracks. Which makes no sense at all. There is no other obvious damage that would appear to be problematic - the thing just won't zoom. Since this is a balancing act between the torque applied by the Zoom Barrel parts and the friction of the spiral grooves, I am wondering it some lubrication was never applied properly and the lens somehow passed final test. That is a stretch though. And I did attempt to lubricate the guides with only a small improvement in movement still far from usable and would likely get twisted out of shape in no time. With the back lens group / aperture assembly removed it operates smooth as silk. The core can even be slipped in place and it will drop right through the barrel with essentially zero friction. They just don't want to play together. The photo in the Web Album labeled "AF-S-DX-18-55mm-ED_Barrel+Core1" (currenty the last one) shows the two parts.

      However, there is a hint of how this may have happened on a working specimen of this lens: Pushing on the flare shield from the back can cause its guide post to pop out of the straight channel in which it moves. And it didn't take much for this to happen. The entire assembly then becomes jammed and if forced could conceivable result in the damage that was present. Fortunately, gently coaxing the post back in the channel with a thin tool returned the lens to full functionality with no hint of any trauma.

      With all the parts installed but still in the unzoomable state, it was reassembled to see what it would do. The results of that test were mixed. It did attempt to focus and would take pictures of sorts, but they were out of focus and strangely colored. At that point the aperture was not operating and the back lens cluster may have fallen out the bottom again. Aside from those issues, everything was perfect. ;( ;-) But it's likely that the electronics are fine. For all the good that does.

      So there are two mysteries here:

      1. Why is it virtually or totally impossible to rotate the zoom ring and have the back lens cluster move smoothly or at all without twisting the zoom and aperture tangs out of shape again even though everything appears to be perfectly aligned and undamaged (after untwisting)? In fact, lens ID #2 requires about the same torque to move zoom through its entire range as this lens does with the back lens cluster totally removed. "It still looks like a lens.". ;-)

      2. Why does the back lens cluster fall out of the guide at the front if zoom is set near 55mm even though it appears to be installed with the correct orientation? This may be a red herring or white elephant or whatever in that so many other things were wrong that with the back shell properly positioned, this may not have been possible.

      If it weren't for (2), perhaps the lack of lubrication would make sense. There must be an obvious cause common to both of these but so far identifying it has proven elusive. This may call for another acrificial lens to compare! ;-) A simple possility is that the destruction resulted in the channels and guides becoming damaged and without the perfect fit, just would not work together.

      Additional photos have been added to the dissection Web Album reflecting the extent to which it has been disassembled, and more info should be forthcoming. Stay tuned.

      The Filter Ring is in mint condition, so it could be swapped into ID #2. But since that would also swap the front lens groups, it is not known whether there might be collateral image quality issues without the Nikon-certified alignment. And since ID #2 is no longer broken, why fix it? ;-)

    Repairing Broken Focus Tabs on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED Zoom Lens

    Neither focus mode worked on this lens (ID #2), zoom was erratic, and if zoomed out with focus at the closeup-end (also extended), the Filter Ring was very loose and would have fallen off if the Trim Ring wasn't preventing that. At first I thought the problem might be similar to the one described in the section: Repairing Loose Front on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens.

    Autofocus on this lens as well as the AF-S VR (and probably the AF-S ED II), and other lenses use the SWM to rotate a plastic ring with two prongs (tips of a fork) that slip into slots in the Filter Ring, which serves to adjust focus by moving in and out via internal helical grooves. On this sample of the AF-S ED lens, two of the raised bits of plastic that are the stops on one side of the slots were sheared off. While they aren't that large, it still isn't clear how this could happen. Possibly a gorilla attempted to change focus using the Filter Ring while in autofocus mode. Or perhaps there was a control problem resulting in the fork bashing against one end repeatedly. However, testing after the repair (below) did not indicate any such issue.

    The broken protrusions are only about 1/16" on a side. But a replacement can be long since there is nothing in the way around the periphery of the Filter Ring. However, gluing plastic is always dicey so I opted to install a pair of 0-80 x 1/16" cap head screws in place of the broken-off plastic bits.

    Since the repair manual is fairly detailed for this lens, it may come in handy here to clarify the disassembly/reassembly process.

    1. Remove the Rubber Grip by carefully lifting one edge and then pulling it off incrementally around its periphery.

    2. Peel off the strip of polyester tape securing the Trim Ring to the Zoom Barrel. It may be possible to re-use this but don't count on it.

    3. Set the AF A/M switch to "M" and rotate the Focus Ring clockwise to the fully extended position. Set the AF A/M switch to "A" so it stays there.

    4. Set zoom to the 55mm position.

    5. Slide the Trim Ring away from the body of the lens so it rests against the Filter Mount at the front.

    6. Check the position of the two tips of the plastic "fork" that engage the outside of the Filter Ring. With these zoom and focus settings, they should be barely on the Filter Ring (<1/8th inch). In the case of this failure, they may be at almost any location and the Filter Ring can be removed now if it doesn't just fall out on its own.

       Nikon AF-S DX Nikkor 18-55mm 1:3.5-5.6G ED Zoom Lens Filter Ring Focus Repair shows the normal appearance and after the repair. Sorry, I forgot to take a pic of the original condition. :( ;-)

       If they are correctly engaged, the problem is elsewhere.

    7. The Trim Ring can be removed from the Filter Ring by carefully squeezing the Filter Ring at the slot positions so they clear the inside of the Trim Ring. But again, this is not necessary.

    8. Inspect the slots in the Filter Ring for the missing protrusions. Two or more of them will likely be sheared off. If only one was broken, the lens would probably still work.

    9. (Optional) Before doing the repair itself, it is possible to somewhat check the autofocus electronics are functional even without the Filter Ring (with the front lens groups) installed. Depending on zoom position, the lens will create a fairly sharp image at extreme closeup - an inch or two from the front of the Zoom Barrel - what's left of the lens. So with the lens mounted on a camera and the Focus Switch set to A, determine the approximate distance where the image appears sharp in the viewfinder and position the camera there. While pressing the shutter button half-way to enable autofocus, move the camera back and forth around that position and observe the operation of the Focus Fork: It should rotate back and forth as well. If it does nothing or consistently slams to one end, then there is something else wrong and that may have been what caused the physical failure in the first place.

    10. Drill a 3/64" hole (which is the correct size for an 0-80 machine screw) in the area where the missing bit would be so that the edge of the screw head will be positioned where the edge of the plastic protrusion was.

    11. Since the plastic is soft, tapping the 0-80 holes may not be needed and in fact using the screws to make tap their own threads may be more secure. In leu of an 0-80 screw, an extra camera or lens screw of appropriate size may be used.

    12. Install the 0-80 x 1/16" screws just snug. Don't over-tighten or there is a risk of stripping the threads.

    13. This step is only necessary if the Trim Ring was removed entirely from the Filter ring: Slip the Trim Ring onto the Filter ring by squeezing it slightly at the area of the slots. Do not secure it. Take care not to dislodge the padded strip on the inner surface of the Trim Ring. If a portion needs to be reattached, it and the surface of the ring should be cleaned with degreaser to remove residual oil and/or grease. If the dangling piece is short, just cutting it off will suffice.

    14. With the zoom and focus still in the extended position, install the Filter Ring so the fork engages the repaired slots. The tips of the fork should just engage them. On the AF-S ED lens (unlike the AF-S VR lens), the Filter Ring can go in at many orientations; only one is correct and the Filter Ring should slip in with no resistance at all. The repair manual shows a reference line on the Filter Ring that should be near a triangular mark on the Helicoid (inner) Ring when they engage correctly. The triangle is easy to spot but the line is just barely visible at the edge of the Filter Ring. And even when found, it is still a bit of hit-or-miss to get the engagement correct. Once engaged, it may make snapping into position easier if focus is set to M and the Focus Fork is rotated slightly counterclockwise so the Filter Ring is recessed a bit when they engage. Depending on which bits of plastic were broken and thus where the screws are located, it may be necessary carefully spread the fork apart to do this. Focus will only work from end-to-end with the correct alignment. It may be worth adding your own reference marks if future repairs are required.

    15. Testing can now be performed both off and on camera.

        CAUTION: Do the testing over a padded surface in case the orientation of the Filter ring is not correct as it may pop off during auto or manual focusing and fall out. That has happened to me a couple of times fortunately resulting in only minor cosmetic damage but it could have been much worse. ;-(

    16. First check that the Filter Ring does not fall off even at the extremes of zoom with focus set to M.

    17. Install the lens on a compatible camera. All functions should work so exercise zoom with auto and manual focus and take some photos and inspect them carefully for sharpness. If focus lock cannot be achieved over the full range of zoom and distance or anywhere, the orientation is incorrect. Recheck it!

    18. Once this test had been confirmed, add a dab of Epoxy to secure each screw. This is best done with the Filter Ring again removed from the lens (Uh!) so as not to get adhesive on the Focus Fork tines or elsewhere. To add some strength, the Epoxy can be extended around the periphery of the ring away from the slots, but not much toward the front. And take care it doesn't dribble where it shouldn't. :( ;-) Confirm that the tines of the Focus Fork will fit in the slots and trim any excess adhesive as required. For reference, the slots are around 9 mm across.

    19. Once the adhesive has set, use an air bulb and/or camel's hair brush to dust out the inside of the lens and Filter Ring, and particularly the exposed lens elements. Then reinstall the Filter Ring as before and reconfirm it is oriented correctly as before!

    20. The remaining steps are the reverse of the disassembly. If the polyester tape cannot be reused, Kapton electrical insulating tape or even thin plastic packing tape should be satisfactory since the Trim Ring is mostly cosmetic, doesn't serve any critical function, and is under minimal stress. Clean the area where the tape goes both on the Zoom Barrel and Trim Ring before replacing it.

    There was some free play when this lens was reassembled because the 0-80 screws weren't quite positioned perfectly. Can you believe that? Geez, they are at least as large a grain of rice. ;-) Also, the heads of the only suitable screws available were ridged, not smooth and after 10,000 years of continuous shooting that could conceivably result in excessive wear of the Focus Fork tines. Of course as a practical matter, neither would likely make the slightest difference in anything including the longevity of the Universe, but being somewhat OCD about such things, a layer of Epoxy was added around the screw heads to to smooth and fatten them up a bit. ;-)

    After around the fiftieth time removing and replacing the Filter Ring, it becomes almost trivial. ;-)

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED II Zoom Lens

    I have not found a repair manual or even an exploded parts diagram for this lens, only the boring user manual. If anyone has one, please contact me via the Sci.Electronics.Repair FAQ Email Links Page. The differences between the ED and ED II lenses are fairly significant so the repair manual for the ED version may not even be useful for the gross anatomy. ;-)

    The ED II is the successor to the ED. Originally I though it may be closer in mechanical design to the AF-S DX 18-55G VR that followed. However, that turns out NOT to be the case. In fact, while the shape of the outer housings (Zoom Ring and Fixed Shell resemble those of the VR, internally, the core optics assembly appears to be identical to that of the ED physically at least and it is swappable between them. Whether the actual lens elements there and in the front lens cluster are any different is not known. The major change is that a single PCB replaces the 3 PCBs in the ED lens. Both the ED and ED II have only 2 lens clusters and for that reason, changing zoom requires noticeably less effort than for the lenses that followed. At least for the functional samples I have (which excludes ID #4, below). In fact, these may barely hold zoom if oriented vertically.

    Investigation of this lens in greater detail can now proceed as a suitable sacrificial specimen has been acquired. ID #4 is in dreadful enough shape mechanically with parts missing that only low cost chants and incantations to the gods of dead camera lenses have been required.

    See the Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED II Zoom Lens Dissection Web Album. There is no dissection yet but it shows some stock photos, the optical architecture, how the lens groups move with zoom, and photos of the exterior and with it partially unclothed in various poses.

    • ID #1 (SN: US6713943): Fully functional.

    • ID #2 (SN: US6598975): Fully functional...

    • ID #3 (SN: US6082727): Fully functional. Slight deterioration and peeling of silver trim strip...

    • ID #4 (SN: US6357413): Bayonet Mount and other parts lost supposedly by a toddler who attempted to disassemble the lens - possibly one with a height of 6 feet 2 inches and weight of 195 pounds. ;-) This should be the perfect lens for dissection. Some parts are missing including the Bayonet Mount, Inner Ring, and Flare Shield. The Camera Contact strip was ripped off and the tangs that operate zoom were twisted out of shape. But one can't have everything at once. In fact, the damage resembles that of the ED lens ID #3. Straightening out the tangs enabled zoom to work but it's tight and requires jiggling to zoom in. However, that's more than can be said for ED ID #3.

    • ID #5 (SN: US7693716): The SWM was stuck and required a prod using a small Jeweler's screwdriver through the switch hole. The label was distressed so the one from ID #4 was installed in its place Missing silver trim strip. Now appears to be fully functional but whether it will not get stuck again if unused for awhile is not known...

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens

    This may have been the most popular of the kit lenses, at least based on which model show up on eBay most often. ;-)

    There is a repair manual on-line for this lens. Search for "Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6 VR Zoom Lens Repair Manual" (without the quotes). It's the first hit using Google.

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Description

    The following applies directly to the Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens and probably somewhat to the non-VR AF-S DX Nikkor 18-55mm f/3.5-5.6G ED II. But NOT to the original AF-S ED version, which differs substantially.

    This was the "standard" lens on older D3xxx, D5xxx, and other low to mid range Nikon DSLRs using the DX format (~1x0.6 inch) sensor But there seems to be little standardization among lenses that may appear to be very similar like the AF-S 18-55mm and 18-70mm, which have very little in common in terms of construction. The AF-S 18-55mm has now been replaced with the AF-P version which uses a different type of autofocus motor which simplifies the construction, and is slightly more compact. A description and dissection of that lens is later in this document. But while larger lenses like the 18-200mm are generally similar in construction, the details will differ substantially. A section on those may be forthcoming but even totally broken ones tend to have a cost on eBay above my curiosity quotient. ;-) And there is a Nikon repair manual on-line for the older version of that lens (non-VR-II).

    Further, many lenses like the one in this section are made largely of plastic. The only major structural part made of metal is the cylinder with tracks to guide the extension of the focus and zoom lens groups. (Right of center in the photo above.) And the more recent lenses (AF-S VR II and AF-P VR) have even replaced that with plastic. So it's easy to break parts or strip threads for tiny screws. In fact, the guide rollers which control the extension of the focus and zoom lens groups are plastic, and at least one was found to be fractured in the discombobulated lens used for the photos. It can be seen among the pile of teeny hardware bits.

    But these are very high tech devices.

    Most of the photos referenced below are also available as a Web Album (though possibly at slightly lower resolution) at Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Parts Web Album.

    • To get an initial idea of what's involved, see Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens - Intact and Disassembled. An intact lens is on the far left. Everything else is from an identical model that was taken apart. And not all parts are present in the photo. Can you figure out what might be missing? Hint: It isn't small. ;-) And some major sub-assemblies have not be broken down to their component parts yet like the focus motor with gear reduction and the cylinder with 2nd and 3rd lens groups and VR assembly! BTW, if the focus motor assembly is removed, the white pinion gear will likely fall off and roll away somewhere never to be seen again so make sure to put it somewhere safe.

      There are a pair of Epson MEMS-based "XV-3500CB High-Performance Low-Power Yaw Rate Gyro Sensors" to provide the signals for pitch and yaw from which the feedback electronics can drive the VR actuators. The two 8 pin chips can be seen attached to the large cylinder physically 90 degrees apart, near the right-side in the photo above.

      Angle encoders for focus and zoom consist of gold-plated patterns with spring contacts to tell the micro-brain what the approximate settings are. These would be used by the control system to know which direction to be able to move and to adjust feedback parameters like loop gain. They can be seen attached to the same assembly as the MEMS sensors are on. The patterns are designed so that no more than one transition can occur simultaneously to avoid ambiguity, though they do not use the common Gray code. This was probably done to minimize the number of patterns or stripes and thus conductive brushes. Those in the Nikkor AF-S DX 18-55mm VR or VR II lenses have 6 data bits but only 2 or 3 conductive stripes (plus a common stripe) providing fewer than half the possible states. More on this below.

    • Most of the electronics are on a pair of PCBs as shown in Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Autofocus / Vibration Reduction CPU & POW PCBs. The larger PCB (labeled "CPU") is 1-9/16x3/4 inches and includes three LSI chips, most likely custom, one of which is in a QFP package with 100 pins. The smaller PCB labeled "POW" is 1-3/8x3/4 inches and includes a CD4050A CMOS Hex Buffer and what appear to be a ferrite inductor and two step-up transformers which drive the PZT motor (see below). There are a few additional support chips as well as 7 flex cable connectors and a pair of 22 pin inter-board connectors. The flex cables are for the contacts to the camera body, zoom encoder, focus encoder, VR gyros, VR drive, VR Hall-effect sensors, and possibly the AF and VR ON/OFF switches. The high voltage for the focus motor is connected via soldered wires. There are an 20 pin pattern of solder pads for an additional 20 pin IC, possible purpose unknown. It's not just a spare location.

    • In order to keep track of the position of focus and zoom, there are a pair of digital encoders - gold patterns on a flex PCB and gold-plated brushes. See: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Focus and Zoom Encoders, and VR Gyros. The encoders are probably used both to know where the limits of travel are and to tune the loop parameters for autofocus and VR, respectively. Unlike standard position or rotary encoders, they do NOT use a classic Gray code, but they ARE distance-1 codes in that only a single bit changes at any boundary. The layout is clever with the contact strips for the bits being intermingled rather than separate, which requires only 2 or 3 brushes for the 6 bits of data all shorted together to a common brush and connected to nothing else. Thus the encoder is more compact with no moving wires/flex cables) and less opportunity to screw up. This may be why the code has 6 bits instead of what is required for the number of states. I'm not *that* determined to figure out the details - perhaps stuff like this is covered in Encoder Design 101. ;-) The bit ordering in the diagrams is arbitrary (LSB to MSB at with reference to the common contact). Nikon could specify it very differently, but since the encoder bit values are probably mapped to numeric values using a lookup table and not used directly for anything, it is irrelevant.

      For reference, here is the standard Gray code for six bits:

       Dec Binary   Gray   Dec Binary   Gray   Dec Binary   Gray   Dec Binary   Gray
      --------------------------------------------------------------------------------
        0  000000  000000  16  010000  011000  32  100000  110000  48  110000  101000
        1  000001  000001  17  010001  011001  33  100001  110001  49  110001  101001
        2  000010  000011  18  010010  011011  34  100010  110011  50  110010  101011
        3  000011  000010  19  010011  011010  35  100011  110010  51  110011  101010
        4  000100  000110  20  010100  011110  36  100100  110110  52  110100  101110
        5  000101  000111  21  010101  011111  37  100101  110111  53  110101  101111
        6  000110  000101  22  010110  011101  38  100110  110101  54  110110  101101
        7  000111  000100  23  010111  011100  39  100111  110100  55  110111  101100
        8  001000  001100  24  011000  010100  40  101000  111100  56  111000  100100
        9  001001  001101  25  011001  010101  41  101001  111101  57  111001  100101
       10  001010  001111  26  011010  010111  42  101010  111111  58  111010  100111
       11  001011  001110  27  011011  010110  43  101011  111110  59  111011  100110
       12  001100  001010  28  011100  010010  44  101100  111010  60  111100  100010
       13  001101  001011  29  011101  010011  45  101101  111011  61  111101  100011
       14  001110  001001  30  011110  010001  46  101110  111001  62  111110  100001
       15  001111  001000  31  011111  010000  47  101111  111000  63  111111  100000
      

      Here is a closeup of the actual focus encoder color coded and labeled with the binary value at each position: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Focus Encoder Coding. While it has 6 bits, there are only 29 states. Interestingly, the codes for the near and far end-zones are complements of each-other, which is probably a coincidence but perhaps not. ;-)

      The Zoom encoder is longer because the Zoom Barrel moves over a larger angle than the Focus Ring, but it's also wider. Here is a closeup of the actual zoom encoder color coded and labeled with the binary value at each position: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Zoom Encoder Coding. Like the focus encoder, it is a distance-1 code (but not the same one) with 6 bits but only 31 states. The common contact is on the opposite side of the coding strips for some unfathomable reason, the relative lengths of each code segment along its length may also differ, the code sequence is not the same (even accounting for the strip position swap), and there is a larger number of states. Aside from all the differences, everything is identical. ;-) Note that since the photo of the zoom encoder strip was taken in situ and it covers a large angle, the areas near the ends are squashed by perspective - the codes should be more spread out than they appear there.

      What isn't clear is why the patterns are non-uniform. It would make sense for them to not have a relative spacing based on the sensitivity to change depending on the focus or zoom position. But all the encoders so far analyzed have seemingly arbitrary variable spacing. Further, in comparing the patterns for several AF-S lenses, no two are the same (even accounting for the required length and available space). Since the code is almost certainly mapped through a lookup table, the absolute values should not be relevant. Go figure. ;-)

      Movement of the lens elements for autofocus in these AF-S lenses doesn't use a conventional motor with magnets and coils like in the good old days. ;-) Rather it uses a motor based on the piezo-electric effect, which is property of some types of crystals to deform when a voltage is applied. The most commonly used crystal is lead zirconate titanate (Pb[Zr(x)Ti(1-x)]O3), usually abbreviated "PZT". This is the same stuff used for the obnoxious beeper elements found in all sorts of electronics. PZT may also be used as an abbreviation for PieZo Transducer, the device itself, which is convenient. ;-) The focus motor is driven at a frequency beyond the range of human hearing and thus similar technology is called "Ultrasonic" by other manufacturers based on the name for the actual motor technology. (Some are called "Hypersonic" which makes no sense at all.....) So focusing should be very quiet - except perhaps for the bats you're attempting to film. ;-) (The "S" in AF-S supposedly stands for "Silent", so all AF-S lenses should use similar technology. However, even if the motor itself is silent, the gears still makes a sound and other parts of the lens may not be quite silent. Nikon calls them: "Compact SWM","Gear SWM", or "Micromotor SWM" where "SWM" stands for "Silent Wave Motor". Much more on this below. Upon first examination, the motor in the AF-S lens appeared to be very strange without any detectable magnetic field and with the rotor almost locked in position, held in place against a plate by a strong spring, more like a clutch than a motor. Furthermore, all combinations of the red/yellow/black wires tested open and applying low voltages to them resulted in absolutely nothing, not even smoke. ;-)

      There are two types of ultrasonic piezo motors used in Nikon lenses: Gear motors and Ring Motors. Piezo motors have advantages and deficiencies. For a brief description with photos (but little explanation), see Two types of motors 'Nikon SWM' (RADOJUVA). In this document, the acronym "SWM" will usually refer to the gear motor variety.

    • Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Piezo Motor and Optical Tachometer Assembly Components to move the focus ring and keep track of its speed. The piezo motor requires two phase high voltage drive, thus the pair of transformers on the POW PCB, above. Velocity feedback uses a slotted disk with an LED/photodiode detector - the right-most gear and the squarish black object at the lower right, respectively. Since focus position is sensed using the angle encoder, it is not needed here. The black covering on the cable to the piezo motor is simply tape to insulate a set of gold traces for slotting into a connector, presumably an alternative to the solder.

    • Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Autofocus Drive Assembly and Piezo Motor Parts shows the gory details. The yellow and red wires go to the upper and lower sets of 4 PZT segments, respectively. The common black wire goes to the slotted metal stator via the gray glob of conductive adhesive bridge. The stator's peaks are in direct contact with the raised rim of the rotor. When a suitable drive is applied to the two input phases (red to black and yellow to black) at the mechanical resonant frequency of the structure, portions of the PZT disc expand and contract at a microscopic level. Each cycle results in only a sub-micron deformation and movement, thus requiring the high frequency drive to do anything useful for focusing. As can be seen in the lower-right photo, there is damage due to wear and/or contamination. ;( ;-) It almost looks like a hard drive head crash! But unlike a hard drive, these surfaces are not separated by a microscopic air cushion, though they do effectively float on top of each-other during operation. More below.

      CAUTION: If disassembled for cleaning, take care using a solvent in the area of the conductive adhesive bridge. Even isopropyl alcohol may remove it. A suitable conductive adhesive is expensive for the tiny amount needed. ;( ;-) Perhaps a couple loops of fine bare wire wrapped around the stator and tensioned would be a suitable substitute.

      Gears are still needed to provide adequate torque to rotate the focus ring reliably, around 3:1 down from the motor to the white pinion gear. The ratio is around 1:3 up from the motor to the slotted tachometer disk. Count the number of teeth on each gear for precise values. ;-)

      The capacitance of each of the two phases was measured to be approximately 1.3 nF. Attempting to drive the motor with a function generator and 1 nF capacitor in series with one of the inputs to shift its phase resulted in absolutely nothing happening at the ~20 V p-p maximum output of the function generator over a range of less than 1 kHz to greater than 100 kHz. So actual high voltage is needed. Measuring the voltage on this lens is regrettably not viable since it's in bits now and was never in a usable state even before it was disassembled. More later.

      However, guessing that there would be enough leakage from the high voltage components, a sense coil was constructed using a 3 turns of hookup wire and connected to an oscilloscope probe. It was then possible to easily measure the PZT drive frequency for a similar lens. The coil was simply placed under the lens - which turns out to be approximately where the piezo motor and POW PCB are located. A distorted triangle wave with a constant frequency of around 77 kHz and amplitude of over 80 mV p-p appeared on the scope only when the focus ring was moving. The waveform shape changed slightly based on direction, but who knows how the coupling (which is probably mostly from the ferrite transformers) affects it. So 77 kHz does indeed qualify as ultrasonic. ;-)

      (In fact during inspection of the innards of the AF-S 55-200mm VR lens described along with a dissection in a later section, the two signals were brought out so they could be measured with the lens on a camera. The voltage turns out to be approximately 240 V p-p at around 70 kHz so it's not surprising that 20 V p-p from the function generator did squat. This lens uses the same or a very similar SWM so the amplitude should be similar. The slight difference in frequency is probably of no significance. The Nikon lens designers like to play with the SWM frequency even among lenses that are physically similar.) One Phase of AF-S SWM Drive Waveforms. shows the actual measured waveform for one of the phases. Since only one of those signals was working, here are Example Nikkor AF-S SWM Drive Waveforms for Phases A and B with both present. The direction of rotation is determined by the relative phase of the two signals where A leads by 90 degrees or lags by 90 degrees. One waveform was actually measured while the other was MSPainted in. ;-) If and when this lens is repaired, actual waveforms for both phases will replace these. Nah. ;-)

      Using a sense coil and scope may be a decent diagnostic test to determine if AF-S autofocus failure is due to a mechanical problem or lack of the PZT drive signals. If no signal can be detected, or if there is only one phase, then it's probably an electronics or control problem. While what is sensed through the air will not be as clean as the directly measured waveforms and determining if both phases are present will be more challenging even if an identical sample of a working lens is available, the presence of a strong signal is indication that most of the circuitry is working.

      Perhaps the key to understanding how this works lies in the "W" of SWM - Silent Wave Motor. This type appears to be what's called an "Ultrasonic Motor" operating at the resonant frequency of the structure, around 77 kHz as measured above. Each set of 4 segments connected to the same input lead if duplicated around the stator would result in a total of 8 more or less equally spaced equal length segments. The two sets appear to be physically offset by 90 degrees. Each set if driven by itself would create a standing wave around the stator. But if both sets are driven the result is a traveling wave whose direction depends on their relative phase with a net torque in that direction. Another way to think about it is with an analogy to those magnet and coil motors, specifically two-phase induction motors. These have two sets of coils that are offset from each-other physically by 90 degrees. The relative electrical phase of the power applied to the two coils then determines torque and direction of rotation. The reasons for the conclusion with respect to this piezo motor are (1) the diagrams and photos of ultrasonic motors from a Web search have a similar slotted architecture, (2) they also have only 3 connections, and (3) the explanation in Survey of the Various Operating Principles of Ultrasonic Piezomotors, K. Spanner seems to fit. But the details are still somewhat of a mystery. Nikon has a bazillion patents on autofocus using the SWM, mostly Japanese though Google does a half decent of translation. Two US patents are US8035906B2 and US20200350838A1 which seem to be close in appearance to this motor, even down to the number of segments on the slotted disk and precise pattern of the PZT elements. These come up or are referenced when searching Google Patents for: Nikon "Silent Wave Motor". Reading patents is always a treat though. :( ;-) If anyone can shed more light on the principles of this motor, please contact me via the Sci.Electronics.Repair FAQ Email Links Page.

      Interestingly, the repair manuals for all the AF-S lenses found on-line make a specific note to not touch the area of the piezo motor. With high voltage involved, that may be good advice, but this in reference to disassembly and reassembly where the lens is un-powered. So, it probably really refers to avoiding contamination which may cause electrical leakage and a reduction in drive voltage as well as possible actual damage "gumming up of the works" after running a long time like what is seen here. Perhaps that is why AF-S lenses have a reputation for autofocus failure - with no sealing of any kind, dampness is getting in over time providing a leakage path so the motor eventually stops working reliably. This lens almost certainly had that failure.

      One subsequent observation is that the drive frequency may need to be tuned to the specific SWM. Even identical lenses may have slightly different drive frequencies and the reason became obvious when constructing an Silent Wave Motor (SWM) Test Rig which provides a way to drive the SWM disconnected from the lens. The sensitivity to drive voltage is a strong function of frequency. What this means is that swapping the POW PCB (which generates the high voltage SWM drive) or even the CPU PCB between lenses may result in sub-optimal performance or no function at all.

    As if that wasn't exciting enough, here is the good (VR) stuff. ;-)

    • Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens 2nd Lens Group, Aperture, 3rd Lens Group in VR Assembly, and Housing shows the partially disassembled cylinder housing these components (left of center in the photo above). From left to right are the 2nd lens group, aperture (iris diaphragm), 3rd lens group, and cylinder housing. The 3rd lens group is the interesting one since that has the actual VR mechanism including voice coil actuators and position/velocity feedback sensors. But the 3rd lens group may only have a single lens element (though it may be an achromat).

    • Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Vibration Reduction Assembly with 3rd Lens Group - Exterior shows how it looks from the outside.

      Left photo: Solder globs for the fat traces to the two coils that move the lens are visible at the bottom and left. The set of 6 fine traces appear to be for a pair of Hall-effect sensors (stuck under the Kapton bumps at the top and right positions).

      Right photo: Solder globs for the fat traces to the locking coil (see below) are visible at the top. The metal plate is one of the magnet pole pieces.

    • Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Vibration Reduction Assembly with 3rd Lens Group - Interior shows how it looks when split in half. Don't worry, no parts needed to be sacrificed in the interest of this dissection! ;-) But the external flex cables have been removed.

      Left photo: The two coils that move the 3rd group lens element are readily visible. There is a rare earth magnet under each of the coils. A quick test with a 2 V power supply confirmed that the lens does indeed move from side-to-side in two axes as expected, but doesn't tilt. Two springs to keep the lens in place are also visible at the upper-right and lower left. The metal squares at the top and left are glued to rare earth magnets to bias the Hall-effect sensors which would be located directly behind them if the original flex-cable was still in place. But one of them fell off without any provocation. Gluing metal to plastic doesn't work well. ;( ;-)

      Right photo: The large metal plate acts as a pole piece for both of the lens element positioning coils. A third coil using an additional pair of magnets hidden under the pole piece is used to rotate a collar to keep the movable lens centered and to prevent it from wobbling on its own due to vibration when VR is OFF. The leaf spring to keep it locked without power is visible at the right. The yellowish metal block at the upper-right is probably just a counterweight for this assembly and is probably made of brass to be non-magnetic.

    There must be some pretty fancy footwork going on in the algorithms on that CPU board to actually implement the VR. And the lens element must be maintained centered electronically when VR is on using the Hall-effect sensors for feedback. There is no restoring force so it will tend to sit at the lowest point. When VR is off, it will be more or less centered using the locking collar. The springs only keep it against the surface of the front cover.

    And you thought camera lenses were boring. ;-)

    Here is a summary of the Nikkor 18-55mm AF-S DX f/3.5-5.6G VR lenses I've acquired so far:

    • ID #1 (SN: Unknown): Parts lens, no back shell (so no SN), torn camera contacts and other cables. Used for most of the descriptions and photos, above.

    • ID #2 (SN: Unknown): Parts lens, no back shell (so no SN) and associated parts, no CPU PCB or cable.

    • ID #3 (SN: US20682964): Front impact damage, broken focus ring rollers. Repaired. See the section: Repairing Loose Front on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens. Well worn but mostly functional. Occasionally it autofocus will get stuck but it usually recovers if focusing at a different distance. This may require attention eventually but is likely unrelated to the trauma. VR was intermittent due to dirty VR ON/OFf switch, cleaned.

    • ID #4 (SN: US16591854): Fully functional.

    • ID #5 (SN: US17727024): Damaged focus ring roller and another one missing. Dented label. Replaced the missing roller, need to locate a replacement for the damaged one. Otherwise fully functional with just a bit of roughness changing zoom, probably as a result of the damaged roller. Very quick quiet focus. Will find or make a roller eventually.

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Disassembly

    Referring to the repair manual is probably the simplest way to do a systematic disassembly of this lens down to just above the level of the alunimum Zoom Barrel with the tracks controlling the motion of all 3 lens clusters, and which houses the middle Lens Cluster (with AR). The manual does not go below this point. If putting it back together isn't a requirement, just removing all visible screws along with unsoldering or cutting a few wires and pulling flex cables from their connectors will accomplish the task. ;-) However, there is a specific order in which some parts are removed to really get to the bottom of things without trauma.

    Though I do not have an intact sacrificial lens at present, I will be hunting for one. Of if someone would like to donate one, it will be immortalized. ;-) So, there should be more to come soon.

    It is best to set each subassembly aside along with its screws in a plastic bag or some other safe place. There are at least a half dozen different size/types of screws and using the wrong one can strip a threaded hole. Note: An attempt was made to use names from the repair manual, so some may seem strange. ;-)

    CAUTION: Do NOT remove the back lens group (called the "4th lens-G unit" in the manual) if intending to reassemble the lens into a fully to-spec state unless closeup photos are taken so that can be replaced in exactly the same position. Else it may require Nikon to align it for only 5 times the cost of a replacement lens. It is secured with 3 screws and washers, sealed with something like Loctite™.

    Back of lens

    1. Set zoom to 55mm.

    2. Remove the single securing the Switch Plate, flip it out, and pull the flex cable out of the connector. There is no lock.

    3. Unsolder the Ground Wire from the solder pad on the flex cable. If no soldering equipment or expertise is available, it is also possible to remove the screw securing the Gound Contact assembly from the Outer shell but putting it back in place is challenging and risks breaking the wire. Soldering would be needed repair that.

    4. Remove the 3 small screws around the periphery of the Inner Ring and it.

    5. Remove the 2 securing the Camera Contacts and gently move it toward the center of the lens.

    6. Remove the 3 large screws securing the Bayonet Mount and remove it along with the Spacer Ring(s) taking care not to snag the Camera Contacts.

    7. Remove the Fixed Tube. Set it aside along with the bayonet parts.

    8. Remove the Camera Contacts flex cable by pulling straight out from the connector. There is no lock. Set it aside.

    9. Disconnect the remaining flex cables (except for the white cable) from the CPU PCB. They all pull straight up or out with no locking tabs.

    10. Remove the screw securing the CPU PCB.

    11. Lift the locking lever on the connector and remove the white flex cable.

    Front of lens

    1. Slip a thin piece of plastic under the model label and lift the edge, then work it around to remove the label entirely without scratching the glass. With care it should be possible to put the label back later with at most minimal evidence of trauma.

    2. There are two holes or slots near the edge of the Front Lens Cluster for a spanner wrench. But it is usually not that tight so a thin tool should suffice toe be able to unscrew it counterclockwise (CCW). Set it aside in a safe place.

    3. Remove the Rubber Grip by slipping a thin piece of plastic underneath the front edge so the entire thing can be pulled off. After long use it may stick to the Zoom Barrel from congealed finger oil ;-) but there is no adhesive.

    4. Remove the polyester tape securing the Trim Ring to the Zoom Barrel and remove it.

    5. Set zoom to 55mm.

    6. Set the A/M Focus Switch to M and rotate the Filter Ring clockwise (CW) to the fully extended position. Set the switch back to A to lock the Filter Ring.

    7. The two fork tines of the Segment Gear Tube should be just barely extending into the slots in the Filter Ring. GENTLY spread the fork tines apart so the Filter Ring can be rotated further CW and removed.

    More to come.

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Reassembly (Coming Someday)

    ;-)

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Dissection

    The preliminary set of photos can be found in Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Dissection Web Album. There is no complete dissection yet but it has most of the relevant photos cobbled together from what's left of the 2 "parts" lenses and a nice intact specimen, as well as the stock photos, the optical architecture, and how the lens groups move with zoom. Some key bits are missing like the Fixed Shell since neither of the parts lenses had one. In addition, various flex cables were missing or damaged. And I wasn't thinking about a detailed dissection when disassembling them. So a sacrificial lens will need to be acquired. If someone would like to donate one, it will be immortalized. ;-) These photos were taken using one of my trusty $10 D70s with the repaired VR lens (see the next section) using a pair of 75W incandescent lamps (with the D70 White Balance set to Incandescent) in place of the LED bulbs and fill flash used for most of the previous shoots. Using the incandescent lamps seemed to require less color correction. Most of the photos to follow will as well.

    Repairing Loose Front on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens

    A hard whack to the front of this (and other similar) lenses can fracture one or more of the plastic rollers that guide the front portion of the lens including the Focus Ring and Focus Barrel. The symptoms will be that the front of the lens is very loose but the lens may be somewhat functional, though with erratic autofocus and the quality of the pictures taken with it will be hit or miss. The seller of the lens used for this repair described the issue as "front impact damage", which is accurate.

    The parts are shown in: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Focus/Zoom Guide. The stud with the rollers is secured through the Fixed Barrel of the lens with the screw on the left with the offending roller missing as will likely be the case with this failure. Both are present next to it, and only a roller on the right. I'm calling them "rollers" though it's not clear if they are intended to actually rotate or just slide within the focus and zoom tracks. When fractured, it's likely that some pieces will break free and float around in the lens interior or perhaps fall out through the back.

    This is among the simplest lens repairs not even requiring any precision tools. That is, assuming replacements for the broken plastic pieces are available - most likely only from a sacrificial AF-S 18-55mm VR lens or other similar small lens (though that is probably not very likely given Nikon's tendency to reinvent everything with each new model). In principle, it is possible to fabricate replacements but they probably won't be found on eBay or anywhere else at affordable prices or at all. Also note that there are 2 sizes of these roller thingies on the same shafts in this lens - the larger ones control movement of the Inner Barrel with Lens Groups 4-8 while the smaller size (relevant here) is for Focus. They are not interchangeable. The smaller size is the one needed here unless both are broken. But the procedure for replacing the larger ones may be considerably more involved as they will be captive by the Focus Barrel and likely requires much more extensive and tricky disassembly.

    The broken pieces are at the front of the lens and the disassembly is relatively low risk. For some of this, the repair manual (above) provides help with photographs, but it goes much deeper than needed for this repair, and getting carried away removing stuff can ruin your entire day. It is also NOT even necessary to remove the lens cap, which should be left in place to protect the front glass.

    1. Remove the Rubber Grip by carefully lifting the front edge and pulling it off. If the rubber is healthy, it will not become deformed. But on really old lenses the rubber may be somewhat dead and flabby and may not recover its original dimensions, at least not quickly.

    2. Remove the strip of polyester tape securing the Trim Ring to the Zoom Barrel. It may be possible to re-use this but don't count on it.

    3. Remove the Trim Ring.

    4. Set the AF A/M switch to "M" and rotate the Focus Ring clockwise to the fully extended position. Set the AF A/M switch to "A" so it stays there.

    5. Set zoom to the 55mm position.

    6. Check the position of the two tips of the plastic "fork" that engage the outside of the Filter Ring. They should be barely on the Filter Ring (<1/8th inch). It should then be possible to CAREFULLY spread them apart just enough so the Focus Ring can be rotated further clockwise and removed. If they are any further forward, confirm that the Filter Ring is at the fully extended (closeup) position (fully clockwise) and zoom is at 55mm. Otherwise there is a risk of them breaking when spread apart.

    7. Set zoom to the 18mm position to retract the inner lens groups and make the trouble areas accessible inside the Fixed Barrel, which is part of the main structure of the lens.

       Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Missing Guide Rollers shows a view inside the Zoom Barrel where 2 of the rollers are missing from the ridged studs.

    8. There may be some bits of the broken plastic rollers still on the ridged metal post(s) or bouncing around inside the lens. Shake them out and try to account for all the pieces. But it's possible some or all have escaped out the back.

    9. Using a pair of tweezers, gently slip the replacement roller(s) over the ridged metal post(s). They should be flush with the Focus Barrel inner surface.

    10. Once all the rollers are in place, immediately replace the Focus Ring by slipping it into the helical grooves and rotating it counterclockwise. It should only go in at the correct orientation and move without resistance until it snaps in place. At that point, "Nikon" on the model decal should be near the top of the lens. If it doesn't move easily, one or more of the rollers may be poking out, some roller fragments may still be present, or it's at the wrong (120 degree) orientation - don't force it. Or something else is damaged. Once confirmed, it would be worth adding your own reference marks to identify the correct orientation of the filter ring if future repairs are required.

    11. Check the stability of the focus ring. It should not wobble noticeably. Test that focus and zoom move smoothly and can be adjusted normally over their entire range.

    12. The lens can be mounted on a camera at this point to confirm that it is happy. Test it a all settings of zoom and focus. If focus cannot be achieved close and far at one or the other end of zoom or anywhere, the orientation is probably incorrect. Recheck it!

        CAUTION: Do the initial testing over a padded surface in case the orientation of the Filter ring is not correct as it may pop off during autofocusing and fall out. That has happened a couple of times fortunately resulting in only minor cosmetic damage but it could be much worse. ;-(

    13. The remaining steps are the reverse of the disassembly. If the polyester tape cannot be reused, Kapton electrical insulating tape or even thin plastic packing tape should be satisfactory since the Trim Ring is mostly cosmetic ane doesn't serve any critical function, and is under little stress. Clean the area where the tape goes both on the Zoom Barrel and Trim Ring before replacing it. Take care not to dislodge the padded strip on the inner surface of the Trim Ring which helps to keep out dust. If a portion needs to be reattached, it and the surface of the ring should be cleaned with degreaser to remove residual oil and/or grease.

    One mystery with the lens (ID #3) used for this description is that there were no signs of broken roller bits inside and the lens does not appear to have been opened previously. So they may still be inside somewhere waiting to cause havoc or fell out the back. There was a fair amount of dust inside which says something about the lack of decent seals on these things. ;( ;-)

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens

    I have not found a repair manual or even an exploded parts diagram for this lens, only the boring user manual. If anyone has one, please contact me via the Sci.Electronics.Repair FAQ Email Links Page. The differences between the VR and VR II lenses are fairly significant so the repair manual for the VR version may not even be useful for the gross anatomy. ;-)

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Description

    This is the newer version of the AF-S DX 18-55mm f/3.5-5.6G VR zoom lens. It has a similar (but not identical) optical design but is smaller and lighter with a lock button so it collapses for storage like the AF-P lens, below. It uses the same SWM technology so it was not immediately clear how this could be possible based on size. It is about 15 percent smaller in diameter and slightly shorter. It is barely larger than the AF-P lens and is almost 1/2 inch shorter when zoomed to 55 mm. I originally thought the AF-S VR II might use a worm gear drive like the AF-P lens but with the SWM rather than a stepper. However, that would not explain how the focus ring can move on its own during autofocus operation since the AF-P uses a "fly by wire" control system for manual focus. Hmmmm. ;-)

    Out of curiosity, I puchased a supposedly defective sample of this lens where the trim ring had popped off as shown in: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens with Loose Trim Ring. It looked bad and for that reason the price was right, but was easily repaired. See the section: Repairing Loose Trim Ring on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens.

    While searching for another one to dissect, measurements of the SWM frequency provided a clue as to the design changes. A 6 turn sense coil was placed under the lens, which as before was determined to be the optimal location for a strong signal, probably in close proximity to the ferrite HV transformer(s). Rather than 77 kHz as in the original AF-S lens, the frequency for the AF-S II is around 290 kHz (!!) which was originally assumed to indicate a much smaller motor (though this turns out not to be the case, more below).

    When the focus ring is moving, the pulse width may be up to around 700 ns. But there is still a detectable very stable ~100 ns spike at the same frequency with similar amplitude for several seconds after the camera has beeped indicating that optimal focus has been achieved, not only while the focus ring is moving. So it is likely from the same source and not just pickup from the logic, perhaps a sort of dither to minimize stiction in the mechanism between focus operations.

    But it turns out that the SWM itself appears to be physically identical in both lenses. And the gear reduction is also similar. Then I thought perhaps the higher frequency was selected to be able to smaller magnetic components, but this also turns out not to be the case. So my conclusion now is that the higher frequency may have been selected primarily because it permits faster focusing or because of complaints from local bats. ;-)

    The physical size reduction of the VR II lens is thus accomplished by mostly clever packaging. ;-)

    Here is a summary of the Nikkor 18-55mm AF-S DX f/3.5-5.6G VR II lenses I've acquired so far:

    • ID #1 (SN: 20750167): The lens with the loose trim ring, above, repaired with tape. The good aperture tang was transferred to ID #3 and later replaced with the good one from ID #6 (the dissected lens - it doesn't matter for that lens). It appeared to be fully functional but later testing showed that the VR switch was intermittent, probably dirty contacts. So this lens is what I use mostly on a tripod with a remote shutter release so VR is irrelevant. But it may be listed on eBay so I am not tempted to goi inside again to clean the VR switch!..

    • ID #2 (SN: 22341241): Then I bought another supposedly broken AF-S VR II lens also to dissect if it could not be repaired easily. But nothing was found to be wrong with it except for some crud on the base that looked bad but was easily cleaned up. Zoom may not be quite as smooth as for some other similar lenses but that doesn't seem to affect anything and could just be a sample-to-sample variation. Darn, another working lens. I hate it when that happens. ;-)

    • ID #3 (SN: 22643651): The next supposedly faulty AF-S VR II lens was indeed defective. The plastic tang that operates the aperture (iris diaphragm) broke near its base, and engages only when zoom is below around 24 mm. Discombobulating an otherwise good lens with a known straightforward repair - likely with no hope of reassembly - would be a shame. Good aperture tang from ID #1 installed here. Lock on this one does not work...

    • ID #4 (SN: 22017590): Another supposedly faulty VR II lens was also definitely defective, working only over a part of the focus range. And it's absolutely perfect otherwise. See the section: Autofocus only Works over Limited Range on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens. I'm still hoping to dissect a certifiably dead lens first to become familiar with the innards before attempting repair of this one. But since the aperture tang is fine, that part could be transferred to taped ID #1 which now has the broken tang from ID #3. VR may also not work on this one.

    • ID #5 (SN: 23353989): Fully functional but that is how it was described, so won't help in the search... ;( ;-)

    • ID #6 (SN: 24030966): This is bad enough to go inside (at least somewhat) and possibly totally dreadful. ;-) It is not recognized by a camera and there were white deposits on the rubber focus grip though no where else on the exterior. There is no visible evidence of serious water damage or anything like that and the electrical contacts show continuity to internal components. But there is definite contamination on at least one of the inner surfaces of the rear lens element(s), if those are removed for cleaning, recalibration may be required by Nikon equipment and proprietary software, this is probably similar. Therefore it would almost certainly not stand a chance of meeting factory specs even if functionality could be restored. The only downside to dissection is that after cleaning the rubber, it looks quite nice with the only blemish being some mottling on the silver stripe of the trim ring. ;-) But its destiny is sealed.

    • ID #7 (SN: 23268629): Busted angled Zoom Barrel, missing trim ring, zoom frozen at 18mm, poor thing. :-( There is just the smallest hint of a ding in the filter mount. See: Seriously Whacked Nikon AF-S DX 18-55mm f/1:3.5-5.6G VR II Zoom Lens. It is not possible to correct the cocked Zoom/Focus Barrel without dismantling the lens, if even then. While zoom is frozen, autofocus and VR work great and it will still shoot photos, though they are absolutely totally dreadful. :( ;-) See: Comparison of Photos Taken with Damaged and Normal Nikon AF-S DX 18-55mm f/1:3.5-5.6G VR II Zoom Lenses. While zoom is frozen, autofocus and exposure work fine. And note the very noticeable barrel distortion in both lenses. But that can be digitally corrected so it's a feature not a bug. ;-) Since I already have dissection photos of the VR II, this may be kept for posterity, for a while at least as a lesson for other lenses as to what not to attempt. ;-)

    • ID #8 (SN: 21611339): Aperture tang frozen, Bayonet Mount broken, lens not recognized by camera. Replaced Bayonet Mount with good one from ID #3 but retained aperture tang ring which required some filing but is now good. Still not recognized by camera. ;-( Zoom sometimes gets stuck. Decent condition otherwise. A brain transplant may be attempted at some point if a donor is found. ;-) Then discovered that Camera Contacts cable had broken traces. Replacement of the flex cable appears to have cured it.. ;-)

    • ID #9 (SN: 20367409): Very good cosmetic condition but label is missing and some mottling of silver trim ring. Autofocus is very unreliable with some hunting before giving up. Occasionally it would signal focus lock but even then might not be anywhere near correct focus. Manual focus and VR were OK. Removed main PCB and camera contacts flex-cable to repair #10.

    • ID #10 (SN: 21855040): Excellent cosmetic condition. Not recognized by camera. Swapped in the main PCB from #9 and now autofocus is functional. But VR is unable to initialize, so after double checkiing that all the flex-cables were fully seated, the flex cable for the VR actuators was unplugged and protected with tape. Whether this is actually the best way to disable VR is not known as it would leave the VR lens assembly floating with no active damping. It may have been that the flex-cable and NOT the PCB was the problem as it had a crack and one trace was open. But it is not known if that was something caused when I removed the PCB or a pre-existing condition. The backup cable intended to test this was faulty in the same way. Sold eBay 18-May-2024, $20...

    • ID #11 (SN: 23862955): Angled Zoom Barrel similar to #7. There is definite evidence of an encounter with a hard surface like a concrete floor. But with a bit of friendly persuasion ;-), it was restored to the normal (no pun....) configuration, so the lens functions mechanically with just some minor stiffness when rotating the zoom ring. (This "repair" doesn't appear to be possible with #7.) However, it is not recognized by the camera. Originally I was afraid that the original impact or subsequent unbinding of the the Zoom Barrel might have caused this. (But crooked #7 works fine - it just takes lousy pictures.) But then I found that the flex cable between the Camera Contacts and Main PCB was torn totally in half. This is very likely a result of someone having attempted to go inside without knowing what they were doing. While a damaged cable is common with the AF-S 18-55mm VRII lens, this one was totally severed, which would not likely happen on its own. Usually there is just a small crack at the crook of the "elbow" of the flex cable disables the lens. The flex cable has now been replaced with one from eBay and the lens appears to be back in shape...

    • ID #12 (SN: 20614838): Near perfect mechanical, optical, and cosmetic condition, but totally dead. Comparison resistance readings with a known working lens shown 4 or 5 of the 8 camera contacts to be open. This is most likely a torn cable syndrome case, though the portion of the cable visible from the back appears to be intact. So perhaps the cable is just not seated properly. Indeed, the cable was found to be torn in the usual place. But at first the lens remained totally dead with a replacement cable. It turned out that several of the contacts were not springy as though they had been squashed. Removing each contact and spreading it apart allowed the lens to "spring" to life. However, autofocus is very weak and not usable. Viewing the signals on an oscilloscope via a pickup coil under the lens shows that they are similar in amplitude and shape to those from a working lens. So either the problem is due to contamination of the focus motor or someone lubricated it (which is a NO-NO). It's possible that this was the failure that resulted in someone going inside and messing up the spring contacts and/or tearing the cable. After bringing the lens back from the dead, VR was tested and found to be broken. VR just keeps hunting in X and Y by a very noticeable amount but never settles down. Oh well, that's probably as far as I will go. In all fairness, there is no real evidence that anyone went inside before me, and the torn cable is a know problem with these lenses. The lens is now for sale on eBay if anyone wants a challenge or needs some AF-S 18-55mm VRII optics and other good parts..

    • ID #13 (SN: 22008122): Excellent cosmetic condition including the optics, but slightly angled filter ring. It was probably dropped, (probably along with the camera!) but onto a surface that didn't mar the filter ring in the slightest or the front of the lens was protected by a lens cap, filter, or other attachment. Focus is stuck at around 3 feet, zoom and VR appear to work, like that's real useful. ;( ;-) As long the distance to the subject is around 3 feet with the camera set for manual focus, images will be fairly sharp in the center, but with serious fuzzyness and color fringing near the edges. See: Slightly Whacked Nikon AF-S DX 18-55mm f/1:3.5-5.6G VR II Zoom Lens. And like ID #7 and unlike ID #11, it does not appear possible to correct this without serious disassembly. Removing the front lens group - made more difficult because the lock ring is difficult to rotate due to the plastic being distorted - did not reveal any obvious place to pry without risking more damage. ;( This is just another example for other similar lenses as to what kinds of activities should be avoided. ;-)

    • ID #14 (SN: 24159700): Listed as "Autofocus and aperture functionality are spotty". Well, that was an understatement. This lens is well worn, the trim ring is missing (I didn't catch that in the listing photos), the aperture tang is broken off so the aperture only responds when zoomed out, and it is not recognized by the camera at all. Seams like a parts unit to me. ;( ;-)

    • ID #15 (SN: 20194590): Another lens with an angled Filter Ring. Focus is totally jammed with the Aperture Tang mostly missing. Zoom works great. ;-) In an attempt to get to the bottom of the jam, this lens had to be nearly totally disassembled with only the Filter Ring and Focus Assembly remaining as shown in these two views of the Focus Assembly from Nikon AF-S DX 18-55mm f/3.5-5.6G VR II Zoom Lens #15 with Angled Filter Ring. Based on the positions of the Focus Encoder and magnetic read head, focus was fully extended when the trauma occurred, so the lens must have been whacked on its face. The only way to restore this would be via brute force since no further normal disassembly is possible. So far, this has proven unsuccessful even squeezing it in a vice to expand the stuck area. And forcing it will likely damage the plastic. Perhaps a jig could be fabricated to apply enough uniform pressure to pop it apart. But that may be more trouble than it is worth. And while there has not been any known damage to parts during disassembly, there is also the minor task of putting everything back together and replacing the Aperture Tang. That probably will not happen. ;-)

    • ID #16 (SN: 22807719): Generally good condition, appears to work perfectly. Some housekeeping of gunk in the plastic grooves might be in order...

    • ID #17 (SN: 23377904) Excellent cosmetic condition. Lock does not work from the locked position but zoom is limited to between 18-55. AF and VR OK...

    • ID #18 (SN: 21839243) Very good cosmetic condition but Zoom was sometimes difficult to turn, Lock did not work from the locked position, and something was rattling around inside. ;( ;-) It otherwise functioned perfectly (though VR has not been fully tested). After removing the Rear Cover Ring and with a bit of shaking, one of the guide pegs associated with the Main Zoom Sleeve fell out, having cleanly broken off! Remarkably, when the Rear Cover Ring was re-attached (without the peg!), the lens appears to work perfectly and both of the original problems have disappeared. Movement of the Zoom barrel is smooth without any binding or hessitation, and everything is still very stable. But with the loss of the guide peg, Zoom is now less robust. Only time will tell. This will be reserved as one of my test lenses.

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Disassembly

    CAUTION: The camera contacts flex-cable between the contact strip and main PCB is very susceptible to being torn where it angles over the edge of the PCB. I've seen this visually on two of these lenses, and by testing with an ohmmeter on a third. Whether it is a design flaw or simply due to rough handling during disassembly and reassembly when the camera contact block is freed from the rear mounting plate is not known. But it has been present on 3 VR II lenses, all of which were thought to have dead main PCBs. I attempt to be very gentle when dealing with flex-cables so I cannot imagine these were all from my handling. See the dissection photo of a cracked cable: "AF-S-DX-18-55mm-VRII-Contacts_Cable1" and the two that follow in the Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album. (They are near the center of the photo array.) There is an obvious crack forming inside the elbow of the flex-cable near the contact assembly and several traces may be severed. That sharp inside corner is just asking to be damaged. With the contacts labeled (arbitrarily) pins 1-8 from left-to-right, the fat trace on the left (pin 2) is ground and the one next to it (pin 3) is probably power. But the first trace to be severed (pin 8) is also somewhat thicker than the others. So the PCB may be fine. Carefully inspect the cable under strong magnification. Replacements may be available on eBay but some with AF-S DX 18-55mm VR II. in the listing title are NOT for the correct lens - check the listing photos carefully. I may order a couple and see if they work a miracle. ;-)

    To test a VR II lens (or any lens) for the cracked cable trace malady only requires a DMM and no disassembly. Positino the lens with the camera contacts at the top viewed from the rear of the lens. (This will be the same orientation as in the first and third photos of the cable assembly, above.) Measure between the spring-loaded ground pin at the 9 o'clock position (positive, usually the red lead on a DMM) and each of the contacts (negative, black). If the polarity is wrong, most contacts will read open. The second contact from the left (pin 2) which is directly connected to the ground pin should show continuity (a few ohms at most). The resistance will be high for all the others on a good lens but not open - a few M ohms. Pin 3 which is thought to be power may be lower than the rest. The contact at the right is closest to where the tear occurs, so that will be the first trace to be severed. If it reads open, some others may be broken also. Regardless, it's dead, Jim. :( ;-) Even splicing a single trace on the microscopic flex-cable will be virtually impossible and of questionable reliability since the cable will likely continue to be stressed. For more than one broken trace, forget it. And the PCB needs to be totally removed for any such repair anyhow. And the surgery would be super fiddly work, so the additional expense of any choice 4 letter words must also be taken into account. ;-) Therefore, if your time is worth anything, the ~$10 for a replacement cable is well worth it.

    Now back to business....

    With care, the following procedure may be used to take one of these lenses apart in a (mostly) reversible manner. The only slight exceptions will be a few places where double-sided tape or adhesive is used to secure cables or connectors and they may need to be replaced.

    Note that for the following, the Fixed Barrel, Fixed Shell, Metal Ring/Shims/Insulator/Spacer, and Bayonet Mount are all one structure secured from the back by the 3 larger screws. The Zoom Barrel rotates around the this and the lens clusters/groups move with respect to it.

    Please refer to the Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album and Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Parts Identification. Not everything is labeled but these should be a start.

    Set aside each set of screws with their respective parts as there are several different size and length screws involved here.

    This is from memory so some details may be a bit fuzzy. ;( ;-)

    It is highly recommended that match marks be added at each step where a major piece is removed as the quasi-3-fold symmetry can greatly confuse things. The only part with true 3-fold symmetry may be the Trim Ring. ;-) All the others can be put together correctly or at all with only one specific orientation. And this is a lens so take photos at each step. ;-)

    1. Remove the 3 screws securing the small ring in the center of the bayonet mount and take it off.

    2. Remove the 2 screws securing the Camera Contacts (Ball Strip).

    3. Remove the 3 screws securing the Bayonet Mount and *carefully* take it off without stressing the cable. This is extremely important as I've seen two instances where the flex-cable was damaged and would need to be replaced, including the lens in this dissection. Whether I caused that or it was a pre-existing condition is not known. Repair of the cable may be possible in principle, but would be extremely difficult and very likely unreliable. A torn cable would result in a lens that is not recognized by the camera and make one suspect a bad main PCB (PCB1). The Camera Contacts will remain attached to PCB1 for now.

    4. Lift off the thick metal ring, thin shim ring(s), and plastic spacer/insulator ring. Note that the plastic one goes at the bottom of the stack facing the lens.

    5. The 7th,8th lens groups (back lens cluster) should NOT be removed unless absolutely necessary (for example to clean the front surface of the 7th lens group or the back surface of the 6th lens group). Their position are critical to lens performance and may not be absolutely centered. Specialized instruments and proprietary Nikon software are required to fine tune the position if it gets messed up. Thus this must be restored to where it was originally upon reassembly, so take closeups BEFORE loosening the screws as a position reference. Having said that, to get at the screws, the protective plastic cap must be popped off - it is held in place with double-sticky tape or something similar. There are tiny black plastic washers under the screw heads which presumably serve some important purpose. ;-)

    6. Carefully remove the 4 flex cables from their connectors on the top of PCB1. They pull off with no locking levers. Some have tiny holes into which a thin (but NOT sharp) tool can be inserted to assist in removal. The largest one going to PCB2 has no hole but a thin tool like an unbent paper clip or tooth pick can be inserted under it to aid in pulling it free of PCB1 or PCB2. Two other cables (Camera Contacts and Gyros) are under PCB1 so wait until the next step for them.

    7. Remove the two screws securing PCB1 and gently lift it up, removing the 2 remaining connectors to free it from the Fixed Barrel. A black grounding wire will need to be unsoldered from the PCB. That is the only unsoldering required during disassembly. If unable to deal with solder, leave it attached to PCB1 and set them aside together.

    8. Remove the 2 screws securing the Spring Ground Contact (over the SWM) and its wire. Otherwise, it will interfere with removal of other parts. It also limits Zoom Barrel rotation to 55 which will prevent further disassembly of the main lens barrels and other components.

    9. Slide a thin piece of plastic under the model label on the front of the lens so it can be pulled off. DO NOT use metal as it may scratch the lens. There are small indents around the perimeter of the label where something pointy can be slipped under the ring from the outside to aid in this.

    10. The front lens cluster with the 1st-3rd lens groups can now be removed. There are holes for a spanner wrench for the purpose but it typically isn't that tight so a pointy tool in one of them and care is all that is needed to rotate the locking ring counterclockwise.

        Note that this step isn't absolutely necessary unless replacing it or desiring access to the VR assembly.

    11. Lift up an edge of the rubber grip and pull it off. This can be done without damaging it.

    12. Peel off the strip of clear Gorrila tape securing the trim ring to the Zoom Barrel.

    13. The trim ring can be pulled off.

    14. Rotate the Zoom Barrel to beyond the "55" position which should cause the Fixed Shell to pop off of the Fixed Barrel. As it comes free, the metal Focus A/M switch fork will probably take the small black SWM gear with it. Regardless, remove that gear along with the long focus gear and set them aside so they don't just go flying off to oblivion when you're not paying attention. DO NOT stress the SWM Gear or shaft as it's plastic and can break easily. ;(

    15. It should be possible to slide the Fixed Barrel ~1 inch out of the Zoom Barrel.

    16. The SWM is now accessible and may be taken out if desired by removing 2 screws securing the grounding spring assembly, the 2 screws securing the SWM itself, and detaching its connector.

    17. PCB2 (SWM drive) may be taken off by removing 2 screws. Don't lose the short flex cable that connected it to PCB1.

    18. Remove the single screw securing the Focus Encoder flex cable. DO NOT remove the flex cable from the metal piece.

    19. The Focus Assembly including the Focus Encoder can be pulled off along with the Zoom Shell. Take care not to damage the Focus Encoder Brush as well as the Focus Tachometer magnetic read head.

    20. The Focus Assembly can be separated from the Zoom Shell if desired by removing the 3 screws around its perimeter. This exposes the Focus Encoder strip, brushes, magnetic tachometer stip, and read head. If the flex cable is stuck somewhere, it can be unstuck. ;-)

        CAUTION: The magnetic tachometer read head on the focus assembly is on a miniature metal spring suspension so that it is in contact with the magnetic strip - see the dissection photos. It is easily bent and damaged. Take note of its location and be careful when handling the focus assembly. It can usually be repaired if not deformed too badly. Also, magnetized tools in close proximity to the magnetic strip could erase the magnetic pattern rendering it and the lens useless. There are YouTube videos involving replacing that strip on other lenses but you really don't want to go there. :( ;-) A sufficiently powerful magnet (or tape head demagnetizer) near the lens could conceivably do it as well.

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Resassembly

    This is actually not quite as involved as I originally thought. (And that probably applies to the AF-P and other lenses as well.) The quasi-3-fold symmetry of these lenses makes it more of a challenge as there is only one orientation for most parts that is correct. But most often it isn't quite 120 degrees and screws will only line up with holes in one of the three possible orientations. The Fixed Shell, Fixed Barrel, Zoom Shell, Zoom Barrel, and Focus Assembly all need to line up just right for it to go together properly. The good news is that so far, the half dozen or so flex cables have survived without serious trauma (fingers crossed). They are tougher than originally thought (though various parts lenses on eBay have shown some to be torn). It's usually sufficient to be aware of the cables. Pulling things apart without realizing a cable is involved is where bad things happen.

    If match marks were made during disassembly, this will be a much more straightforward. If not, refer to the dissection photos.

    Please refer to the Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album and Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Parts Identification. Not everything is labeled but these should be a start.

    In all the fussing, the plastic mounting post for the SWM Gear broke off at its base. ;-( Repairing that was a pain but appears to have been successful: A slightly under-size hole was drilled in the stump and then the post was press-fit back in place. For the OCD types, adding a bit of non-softening plastic adhesive would have probably been worthwhile. It's a fraction of an inch shorter than the original but should be good enough for government work, especially considering that I have no intention of actually using this lens - ever!

    Three 2-56 nuts and washers will be required during reassembly which are not part of the lens. These substitute for the metal rings etc. and Bayonet Mount to secure the Fixed Barrel and Fixed Shell with similar thickness until the Bayonet Mount is installed.

    If individual parts like the SWM or PCB2 were removed during disassembly, additonal steps may be required, but they should be self-evident, intuitively obvious, or both. ;-)

    1. Slide the Focus Assembly into the Zoom Shell and secure it with 3 screws. Slip the flex cable for the Focus Encoder and Tachometer through the slot in the between them taking care not to damage it. There is only one of the three orientations where these will mate properly.

    2. Slip this combined unit into the Zoom Barrel with the small dot on the Lens Hood Mount just beyond the 55 mark. The two pegs on the Fixed Barrel and plastic protrusion on the Zoom Shell should slip easily into the pair of tracks on the Zoom Barrel but will not go further.

    3. Gently pull the Fixed Barrel out so it extends as far back as possible.

    4. Replace the Zoom Brush using its screw.

    5. Replace the Focus Gear in the hole in the Fixed shell so that it extends and engages the rotating part of the focus assembly. If it doesn't reach, push the Fixed Barrel in very slightly.

    6. Insert the SWM Gear into the A/M fork on the Fixed Shell. The top has a ridge that will stay in the fork.

    7. Carefully position the Fixed Shell on the Zoom Barrel so the large dot lines up with the small dot on the Lens Hood Mount and just beyond the "55" on the Zoom Barrel. The Fixed Shell and Zoom Barrel should seat flush against each-other as they would be normally. (Later it will lock in place when toward "55".) Take care to avoid damage to the Zoom Brush. The 3 Bayonet Mount holes should line up with the mating holes in the Fixed Barrel and be touching or almost touching, but probably not fully seated.

    8. Place a 2-56 nut and 2-56 washer on each of the screws that attach the Fixed Shell to the Fixed Barrel. Gently thread each of these through the Fixed Shell into their mating holes on the Fixed Barrel to pull them together while attempting to turn the Zoom Barrel. Do not force anything. It should now be possible to rotate the Zoom Barrel normally to the Locked position. The nut and washer are temporary until the remaining parts of the back of the lens are replaced. If the Fixed Shell and Fixed Barrel are too far apart for the screws threads to engage, use only the washers until they can get a solid grip all around and then back them out and add the nuts. The screws should not bottom in the holes. Damage to these threads would be bad since the 3 screws secure the lens to the camera body.

       If the Zoom Barrel doesn't turn easily, use a thin piece of plastic to depress the (now hidden) pegs for lens groups 4,5,6 (middle lens cluster) just enough so they can slip into their tracks inside the Fixed Barrel while gently twisting the entire combined unit counterclockwise. Don't force anything. Didn't I say that already? ;-)

    9. It should now be possible to rotate the Zoom Barrel to the Locked position. Do NOT squeeze the Fixed Shell. Without the Bayonet Mount and associated parts being secured to the Fixed Shell, it will distort making it hard to rotate the Zoom Barrel. There are no precision roller bearings. ;-)

    10. Install the Spring Ground Contact using its 2 screws. This also serves as the zoom stop at the 55-end.

        See: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Final Reassembly. The nuts and washers substitute for the Bayonet Mount and associated parts prior to their installation. The photos show the lens in the Locked position.

    11. The Zoom Barrel should now rotate normally between Locked and 55 but no further with each part of the lens moving as it should. The screws, nuts, and washers installed above can probably be removed safely now since the Zoom Barrel will not be able to rotate past 55 where it could detach, but there is no harm in leaving them in place until final assembly.

    12. Install the Trim Ring so it seats in the six slots. The Trim Ring has 3-fold symettry so it will mate in 3 possible orientation and they are all equivalent. Secure it with the 1/4 inch gorilla-strength tape. ;-) I used Kapton electronic insulating tape but that is probably not optimal. Press the tape in place all around particularly on the 6 tabs.

    13. Slip the Rubber Grip over the front of the lens so it lines up with the Lock Button.

    14. Replace the Front Lens Cluster assembly by rotating it clockwise until it seats against the Focus Assembly. It should be snug but do not overtighten.

    15. Replace the model label. For reference, the left edge of the "D" in "DX" should line up with the dot on the Lens Hood Mount. This is really important! ;-)

    16. Attach the cable from the Camera (CPU) Contacts to the large white connector on the underside (actually the front) of PCB1 paying attention to orientation so the contact unit is oriented correctly. It presses in with no locking lever.

    17. Similarly, attach the Gyro Cable to the small connector on the underside of PCB1

    18. Install PCB1 and secure it with its 2 screws. Take care that none of the protruding flex cables get stuck under the PCB.

    19. Install each of the remaining cables. They press in place with no locking levers. Their locations and orientations should be self evident. ;-) On some, there is a small hole near the end of the cable that can be grabbed by a thin (but NOT sharp) tool to aid in insertion.

    20. Resolder the ground wire from the Spring Ground Contact to the pad on PCB1 if removed during disassembly. Make sure it is routed away from the center where it might get caught during zoom operation.

    21. Remove the 2-56 nuts and washers. DO NOT rotate the Zoom Barrel or pull on the Fixed Shell until the entire thing is secured to the Bayonet Mount.

        The right photo in Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Final Reassembly shows its appearance now.

    22. Replace the plastic insulating ring, shim(s), metal ring, and Bayonet Mount. Slide the Aperture Tang into the Aperture Slot inside the lens and secure the Bayonet Mount and related parts using the 3 large screws.

    23. Confirm that the aperture range goes from min to max. (This shouldn't have changed unless parts were swapped from another lens.)

    24. Carefully position the CPU Contact Block in the Bayonet Mount and secure it with its 2 screws.

    25. Replace the Inner Ring and secure it with its 3 screws.

    That's it! With care, match marks, photos, attention to detail, perseverance, and a bit of luck, the entire disassembly and reassembly process was not impossible and a learning experience. Now the lens should work perfectly if it did originally or if broken parts were replaced. If the lens survived and you survived, the next one will be easier. After the 17th iteration, it will seem totally trivial. ;-)

    While the details for other lenses will differ, the general procedures will have a lot in common and doing this first with a lens like the AF-S DX 18-55mm VR II should provide good experience before tackling a larger expensive one. The key to success is understanding how the motion of the lens clusters is "programmed" by the tracks inside the Fixed Barrel and then being able to install them correctly during reassembly.

    Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album

    All of the photos are available as a Web Album at Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR_II Zoom Lens Dissection Web Album, which will be a more-or-less step-by-step disassembly like that of the camera dissections. So from start to finish it goes from the fully intact lens to the naked parts. ;-) Most photos were taken with a D70 using lens #5 except for a few of the closeups using the Micro Nikkor AF-S DX 40 mm f/2.8G. The original mostly white backgrounds have been allowed to remain for some of the photos since that gives them more of an authentic look. Where they couldn't be bleached adequately via exposure or gamma/contrast adjustment - or just for consistency - the inPixio On-Line Background Removal Tool was used.

    Most of the photos are now present in the Web Album. Except for the first 2 stock photos, all are of lens #6 except for the few showing the back of the lens with the bayonet mount and associated parts removed.

    Other than the front of the 7th lens group and back of the 6th lens group which has some mottling (which was easily removed with 90% isopropyl alcohol), the interior including the PCBs, connectors, SWM, gears, and everything appear to be pristine with no evidence that contamination caused the lens's failure. So perhaps it was zapped by static. And yes I violated my recommendattion to not remove the 7th,8th lens groups but there is really no intention to put this lens back in service.

    Some conclusions so far: The VR II is somewhat cost reduced but in a good way. ;-) For example, only one wire needs to be unsoldered to totally disassemble it to the level of major components. Most flex cables plug into the CPU PCB (PCB1) and are the push-in type with locking levers to break. Many have a small hole near the end of the cable for a thin instrument to aid in removal. There is a minimal number of pieces of double sticky tape or adhesive which would need to be replaced if reassembled.

    Focus implementation is generally similar to that of the AF-S VR lens but the SWM gear train is part of the main structure and NOT a separate assembly. The tachometer and its gears are gone. Speed sensing has been implemented with a magnetic strip as in some other AF-S lenses. The good news is that the SWM itself and the two remaining gears are replaceable without major disassembly.

    The focus encoder coding is of course different than the one in the AF-S VR and all other lenses I've checked. But is that a surprise? ;-) See Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Focus Encoder Coding. This encoder has 6 data bits with 22 states. The spacing almost makes sense being fairly similar in the central region and further apart near the ends. The extra tracks in the photo are pass-through for the magnetic read head.

    The Zoom Encoder does NOT run axially as in the the AF-P 18-55mm VR lens (which has a similar lock button). It runs around the perimeter of the inner surface of the Fixed Shell and is extended to cover the locked area with a constant code. (Take care not to damage the brushes if the Fixed Shell needs to be reomoved.) At the location where it becomes unlocked, there is a very small length where the common conductor extends to the next one over, but that would not result in a different code, so its purpose is mystery. See Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Zoom Encoder Coding. This encoder has 8 data bits with 36 active states and the locked state. In the main portion of the active zoom region, their spacing is similar but not precisely the same. For the locked region, the code is a constant 00110001. Note the 8 data bits rather than 6 data bits for all the other lenses analyzed so far. Yet again, we have a change to the encoder coding and now even the number of bits for no fathomable reason. 6 bits would be plenty. It almost seems as though the designers of these lenses (1) are not privy to documentation on other lenses, (2) have a serious case of NDITD (Not Developed In This Department) syndrome, (3) never heard of lookup tables, (4) are smoke'n sump'n, or (5) all of the above. It makes no sense whatsoever.

    The VR II VR assembly has changed slightly compared to the AF-S VR (I) lens. It is smaller and similar (but not identical) to the one in the AF-P VR lens. As with that one, the Hall sensors are gone so changes in the VR lens group position must be sensed in some other way.

    The state of affairs as depicted in the Web Album is about as far as I intend to go in the disassembly. There are still a few individual parts that have not be removed or reduced to their individual pieces, usually due to issues of reversibility of the procedures, but all key sub-assemblies have been removed and documented. This applies for example to the SWM and VR assembly. There is little point to taking them to bits as that has been done for the 18-55mm AF-S VR and AF-P VR lenses, and they are similar. While nothing had been damaged, restoring the lens to its original condition is probably not going to happen. While there is a small probability that simply reseating the connectors will have cured the "not recognized by the camera syndrome", I'm probably not that determined to find out. And if the CPU PCB (PCB1) is dead, swapping in one from another lens will not work well as VR parameters and other settings need to be optimized for each specific lens using the custom specialized Nikon test instruments and software. However, physically putting it back together seems possible without having mastered a 27 level Rubik's Cube though there are a couple of steps that could be dicey like replacing the Fixed Shell.

    Explanations of the dissection photos will be forthcoming so stay tuned. ;-)

    Parts Naming

    (Some or most of these may not agree with how Nikon sees it as no internal diagrams or parts lists are available.)

    • Fixed Barrel: is the main "chassis" of the lens. It is rigidly secured to the "Fixed Shell" and "Bayonet Mount" which is what attaches the lens to the camera.

    • PCBs 1 and 2: PCB1 has the CPU and related components including VR and AF control. PCB2 has the high voltage driver for the SWM and probably not much else.

    • Front and back or rear: refer to direction with respect to the camera.

    • Lens Group numbering: These correspond to those on the Nikon Web site. The 1st Lens Group is at the front of the lens and the 8th Lens Group is at the back. Lens groups may contain multiple lens elements - the individual glass or plastic optics.

    • Lens clusters: These are my terms for the lens groups that move together when changing the zoom setting. Lens Groups 1,2,3 are in the Front Cluster; Lens Groups 4,5,6 are in the Middle Cluster (with 4,5 being for VR); Lens Groups 7,8 are at the back.

    • Photo filenames: For the direct links, they have the usual DOS-era 8 characters. Sorry. ;-) For the Web Album they all start with "AF-S-DX-1855mm-VRII-" followed by a set of descriptive terms including at least one underscore ("_"). Web Album Generator removes all dashes ("-") but leaves the underscores so that simplifies cleaning up the folder using wilecards at the Command prompt if the need arises. No, I don't run DOS but it just does some basic things much more easily than Windows.

    • View Numbering: This is mostly arbitrary just to distinguish the photos. But where the lens or lens assembly is shown with varying degrees of rotation, #1 for the nameplate, #2 for the switches, #3 for the serial number, and #4 for what's left. But sometimes this is not how it really is and I have absolutely no intention of fixing it. ;-)

    • Original cropped photos: As with the other Web Albums, these may be viewed by copying and pasting the filename at the top of the page into the same folder as the Web Album and adding a ".jpg" (without the quotes) to it. Depending on the specific photo, the resolution may be significantly higher. Web Album Generator has a funny idea of what "Extra Large" means. ;-)

    And should anyone actually read this before the warranty on the Universe expires and has specific questions or requests, I may be contacted via the Sci.Electronics.Repair FAQ Email Links Page.

    Repairing Loose Trim Ring on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens

    Both the AF-S VR and AF-S VR II lenses have a trim ring at the front with a silver stripe. Its main purpose appears to help keep dust out of the mechanism and perhaps stabilize the focus barrel. So replacing it may not be essential but is worthwhile.

    The trim ring is held in place only with a strip of ~1/4 inch tape wrapped around the entire lens. But while the original AF-S VR lens has a decent width area around its entire perimeter for the tape, the AF-S VR II trim ring only has six very narrow tabs that after awhile (or from an impact) can come loose as was the case with the first AF-S VR II lens I acquired (ID #1). See Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens with Loose Trim Ring. It looked really bad and the lens was destined for dissection if repair was not practical. But fixing it simply required removing the rubber grip by lifting it away from the body pulling it off, and then replacing the tape. But Nikon must use tape with super-strong adhesive as ordinary tape probably won't hold for long. So far though it's been behaving with just some Kapton tape, and many of the photos for the camera dissections have been shot using this lens. It might also be possible to use a few dabs of adhesive like 5 Minute Epoxy or industrial strength rubber cement between the trim ring and the barrel it seats against, but this has not be attempted - yet.

    And the racing stripe (which is purely cosmetic) is just a length of really thin metal-coated tape which often detaches at one end. Or corrode as in the case of the lens ID #6 used for the dissection. It can usually just be peeled off if desired, which is a lot easier than attempting to neatly glue it back in place.

    Replacing the Bayonet Mount Parts on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens

    A sharp WHACK or overzealously attempting to attach the lens if not properly engaged can result in fracture of the cheesy plastic bayonet mount. I've also seen one of these lenses with most of the plastic aperture tang inside the lens (that actually moves the iris diaphragm) broken off and missing. (It's not even clear how that can happen.) Assuming replacement parts are available, these and similar issues require the same disassembly steps and are among the few repairs of these sorts of lenses that are possible without a great deal of prior experience.

    This procedure may apply to some other Nikon lenses. But specifically NOT to the similar AF-P lens where removing the CPU contact block screws results in the individual contacts popping out all over the place. ;-(

    A #00 or #000 Philips screwdriver is required for the 3 sizes/types of teeny screws:

    1. Remove 3 screws securing the inner ring to the bayonet mount. These screws have the smallest heads. It should then be possible to pop off the inner ring.

    2. Remove 2 screws, one on either side of the CPU contact block securing it to the bayonet mount. These are very short machine screws.

    3. CAREFULLY work the CPU Contact Block around so it can be freed from the bayonet mount but remain attached via the orange flex cable. It may need to be tilted or angled but there should be enough slack in the cable. DO NOT pull or stress anything! At the very least, the cable can pull free of the connector, which will then require more extensive disassembly of the lens to reattach it. The cable could also tear. ;-(

    4. Remove 3 screws near the edge of the bayonet mount securing it to the lens housing, and can now be removed without disturbing the CPU contact block.

       See Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Bayonet Parts.

       CAUTION: DO NOT attempt to rotate the Zoom Barrel with these screws removed as the whole thing can come apart requiring an order of magnitude greater level of skill to reassemble. Specifically, the Fixed Shell may come free of the Fixed Barrel taking the SWM Gear with it and possibly damaging the Zoom Brush as well as the Focus Assembly and Zoom Barrel popping out the front.

    Individual parts of the bayonet mount can now be replaced if necessary, though this will at least one level up of fiddlyness. ;-)

    Reassemble in reverse order. And don't force anything! All of these are tiny screws so stripping holes is possible. When reinstalling the bayonet mount, carefully insert the aperture tang straight into the plastic receptacle that moves the iris diaphrapm. Unless the bayonet mount is replaced without changes, the setting of the aperture tang may need to be adjusted. It's secured with 2 screws and sealer. I do not know what the official procedure is, but in lieu of that, make sure the aperture tab (that's activated by the camera) just touches the the edge of the cutaway in the inner ring. Then after securing the bayonet mount, confirm that the tab moves smoothly by hand and the aperture goes through its entire range.

    Autofocus only Works Over Limited Range on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens

    The following most likely applies to other AF-S lenses and in part to others. A Web search will turn up cases of generally similar autofocus problems. For example: Focus Hunting Problem in AF-S Nikkor 24-70mm 1:2.8 G ED Zoom Lens and Nikon Lens repair: Broken Autofocus on a AF Nikkor 28-70mm Zoom Lens. These both involved a dirty or damaged encoder to be the cause, similar to my conclusions (below) based on the symptoms prior to internal examination of this lens and before finding these videos. Problems like this do tend to have simple causes.

    This lens (Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II ID #4) works perfectly in all respects from its closest focus to around 2 feet. It will go back and forth between those distances all day without issues. But beyond there, it will never move the focus ring to get closer, and at some point it will jam against the end-stop beyond infinity.

    This is a works in progress but here are some observations:

    • When focus is set to M, if the focus ring is adjusted for close, and returned to A, autofocus will always work reliably from minimum to a couple of feet. Back and forth any number of times as long as the focal point isn't lost so it overshoots to a long distance.

    • Autofocus will work reliably as long as the distance is increased.

    • Beyond a few feet, moving closer will generally fail.

    • At some point the focus ring will mechanically lock where the SWM has caused the gears to jam at the far end-stop. There is then no free play and it's obviously too tight.

    My current hypothesis is that the encoder that reads focus position is either not working correctly or has perhaps become disconnected. So the lens's microbrain is getting confused, poor thing. ;( ;-) Among other things it's not being programmed to provide the necessary torque to focus in from near infinity, and it's overshooting infinity, hitting the end-stop and getting really stuck there. Monitoring of the SWM waveform appears to show that it is trying but almost certainly attempting to rotate the focus ring in the wrong direction. With the high gear ratio, it should have no problem backing away. The only way to unstick it if jammed is to flip the A/M switch back and forth. However, even if not jammed, it will still not focus in from more than around 3 feet to infinity. It will focus reliably from the closest spec'd distance to around 2 feet, though it may overshoot dramatically but doesn't jam. All these lenses sometimes overshoot especially if there little detail in the focus zone.

    Since there is a definite boundary beyond where it screws up, this would appear to rule out an SWM or gear train problem. The SWM rotor and all gears except the one on the focus ring itself go through multiple revolutions over the focus range. The rotor of the SWM itself goes through ~2.75 revolutions for each revolution of the focus ring drive gear and that goes through nearly 2 complete revolutions to move the focus ring from end-to-end.

    So this is probably a control problem. The only inputs to the microbrain are the tachometer (a magnetic strip with read head) and the focus encoder (which senses the absolute position of the focus ring). It's possible the magnetic pattern the tachometer uses has been partially erased, but the most likely cause is the focus encoder: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Focus Encoder Coding with the bits color coded and labeled with the binary value at each position. More on these encoders can be found in the section: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens. But interestingly, the focus encoder in the Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens also has 4 conductive strips and 6 bits, but the coding differs, which really doesn't make any sense unless each new Nikon designer is required to change something as a test. ;-)

    If you're not totally confused, you weren't paying attention. ;-) But to reiterate: It is most likely that the focus encoder is either feeding bad readings to the microcomputer or they are being misinterpreted.

    No doubt disassembly of this lens will be required at some point, to satisfy my curiosity if nothing else. Hopefully the problem will be something obvious like a damaged focus encoder brush, loose connector, or some dirt or soda residue on the encoder strip. ;-) However, based on the dissections (See above), this requires fairly significant surgery, so it may be postponed until Major Medical insurance coverage is available. ;-(

    Repairing Broken SWM Gear Shaft in Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens

    This is the gear between the SWM itself and the Focus Gear that engages the drive gear on the Focus Ring. The shaft is part of the Fixed Barrel and thus made of the same plastic as the structure. While it isn't likely to break during normal use, it can get stressed when going inside to repair something else, particularly during the removal or replacement of the Fixed Shell.

    If it fractured at its base, the original shaft can be reused but if it fractured in the middle, a substitute shaft will be required which can be made of metal. Note that the original shaft is NOT a constant diameter but is thinner at the top. It is not known whether this is essential if a replacement shaft is used. It probably allows for a larger tolerance in the positioning of the metal fork of the Autofocus A/M switch.

    Either way, a hole will need to be drilled perfectly centered and square in the Fixed Barrel so that a replacement shaft can be installed. The diameter at the base is approximately 0.045 inches but this should be confirmed. Ideally it will be a press-fit without requiring adhesive.

    1. Refer to the instructions in the section: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens Disassembly and follow them to the step where the Fixed Shell is removed along with the SWM and Focus Gears.

    2. Arrange for any protruding cables to be well away from the area of the SWM Gear shaft.

    3. Using a drill press and 0.040" bit, very carefully drill a hole to a depth of around 3/32".

    4. Test to see if the broken or replacement shaft will fit the hole. If close, it can be widened with the tip of a needle file or a slightly larger drill bit. But avoid going oversize.

    5. Once the replacement shaft just barely fits in the hole, it can be gently pressed into place. Using a bit of non-softening plastic adhesive may be worthwhile.

    6. Check the fit and then following the reassembly instructions.

    A Tail of Two Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lenses

    These were purchased as "For Parts or Not Working" on eBay and are IDs #9 and #10, above. ID #9 would attempt to focus with some hunting but usually would give up. Sometimes it signaled focus lock but even then it would often not be anywhere near the correct focus. VR appeared to work. ID #10 was not recognized by the camera at all.

    So the plan was to see what would happen if the main PCB from ID #9 was swapped into ID #10. Accessing the main PCBs in these lenses is relatively straightforward. The only annoyances are (1) there is a soldered ground wire and (2) the flex-cable for the gyros is nestled under the PCB and a bit of a pain to get at. But other than those, it's just screws and flex-cables. The transplant was performed without incident. Autofocus appeared to work flawlessly but there was a horizontal "jump" to one side and back in the image in the viewfinder when the camera was powered on indicating an issue with VR. In fact VR appears to be dead after the jump. This probably means it is unable to initialize. It may be that the horizontal gyro is defective or that the aforementioned cable wasn't installed properly (though I rather doubt that). In the end, it was decided to simply unplug the flex-cable for the VR actuator and live with no VR on this lens. That's probably a fair trade. It's also not known how closely matched VR is to the specific lens, so even it VR did work, it might not be optimal. Another observation for lens ID #10 was that one of the metal shims between the plastic ring and lens body was corroded indicating possible water damager, though everything else including the optics appear pristine.

    I was expecting that a swap of the PCB from ID #10 into ID #9 would result in a lens that is not recognized.

    But before then I decided to check for continuity from the camera contact strip to the PCB and discovered that there was an open circuit to the contact at one end. Indeed, the flex-cable is tearing where it passes the edge of the PCB. So I figured I would swap it with a flex-cable from the VR II lens in the dissection which was thought to also have a dead PCB. But that flex-cable, too, is torn. So this must be a common problem. Whether it is caused by rough handling during disassembly or reassembly, or a design flaw is not known. Now I need at least 2 good flex cables for the 18-55mm VR II lens. ;-)

    Replacing Torn Camera Contacts Ribbon Cable in Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens

    This was first done on AF-S 18-55mm VRII lens #11, which originally had a very cockeyed front zoom barrel. That was corrected with some rather un-gentle persuasion and mechanically. The lens appears fine with perhaps just a bit of stiffness over a portion of the zoom range, though probably nothing beyond normal sample-to-sample variation. But the lens was not recognized by the camera. At that point I was sorry I didn't check it before correcting the mechanical issue suspecting that perhaps the "repair" was at fault. However, upon initial interior inspection, it was found that the Camera Contacts Flex Cable was torn cleanly in half. This may have been caused by the previous owner's attempts to repair it though - it could not have been by the trauma or its remedy.

    A crack or even clean break at the crook of the elbow of this ribbon cable appears to be relatively common with these lenses. So common in fact that replacement cables are readily available on eBay, even in two-packs.

    With a bit of care, replacement is straightforward. It is among the simplest of the "in-lens" repairs:

    1. Remove the two screws securing the Camera Contacts Assembly.

       Remove the three screws securing the Trim Ring and take it off.

    2. Set zoom to the 55 mm position. This retracts the rear lens assembly forward so it is out of the way.

    3. If the cable is totally torn, the Camera Contacts Assembly can be removed. And there is no practical way to repair a slightly torn cable even if just a single conductor is severed, so feel free to complete the tear. ;-) However, keeping whatever is left of the cable intact will provide a feel for minimizing stress on it during reassembly.

    4. Remove the three screws securing the Bayonet Mount Ring to the body of the lens. Lift it straight out along with the metal and plastic spacers. Keep them together so their relative orientation won't be lost. Note location of the spring ground contact pin poking up from the main lens assembly and where it goes in the Bayonet Mount Ring and spacers.

    5. Carefully pull off the three small ribbon cables. There are convenient holes in the tabs that may be used. Avoid scratching anything underneath.

    6. Remove the two screws securing the Main PCB.

    7. Lift the Main PCB with the long ribbon cable so it detaches from the socket inside the lens. This may be easier than attempting to pull it off side-ways.

    8. Carefully flip the Main PCB over without detaching the soldered ground wire.

    9. Pull off the remains of the Camera Contacts Ribbon Cable tab. There may be some adhesive to keep the middle portion from moving around.

    To prepare the replacement:

    1. The mating portion of the Camera Contacts Ribbon Cable Assembly has a series of eight gold-plated pads held against the actual metal contacts with a metal locking strip.

    2. With the Camera Contacts facing down, slide the metal strip off to release the ribbon cable. If this is done carefully, the metal contacts won't fly all over the place.

    3. Remove the remains of the old ribbon cable from the locking strip.

    4. Peel off the paper protecting the adhesive over the new ribbon cable and then stick on the locking strip taking care that it is in the same orientation and position.

    5. Slide the locking strip with cable back under the tabs securing it.

    Reassembly of the lens is now just the reverse of disassembly. Zoom should remain set to 55 mm. Take particular care not to stress the flex cable during the process. Or else you'll be doing this all over again. :( ;-)

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens

    I have not found a repair manual or even an exploded diagram for this lens or any other AF-P lens. If anyone has one, please contact me via the Sci.Electronics.Repair FAQ Email Links Page.

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Description

    The following applies directly to the Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens and mostly to the non-VR version as well. If fact, the only way to casually tell the difference is the lack of a "VR" on the body.

    This AF-P lens is optically very similar to the AF-S versions, above, but with one additional lens element. However, it uses the Nikon so-called "Pulse" technology (thus the "P" in AF-P) for autofocus instead of the "Silent Wave Motor" (SWM, or S in AF-S). Pulse autofocus is based on a stepper motor and does indeed appear to be quieter than silent. ;-) While SWM uses a piezo motor driven at an ultrasonic frequency (above human hearing) which in itself should be very quiet, the motor's rotating surface plate in contact with the actual PZT element, associated gear train, and other rotating parts makes detectable noise.

    So AF-P lenses return to motor technology with magnets and coils. ;-) As noted above, the "P" is supposed to stand for "Pulse", which kind of applies. They are claimed to be even quieter than AF-S lenses and that is probably true. The manufacturing cost is also much lower. ;-) And there have been comments on various forums about AF-S autofocus reliability, which is quite credible given their complexity and opportunities for contamination to get to the motor. And that they run on several hundred volts! So perhaps a little of both. Replacing the piezo motor with a stepper motor also allows the AF-P lens to be more compact since the motor itself is less bulky and the high voltage drive components and gear train are eliminated.

    However, AF-P lenses are not compatible with the D5100 or D3200 (or earlier) cameras that are happy with AF-S lenses. Others like the D5200 may need a firmware upgrade (but that is a free download). And since there is no VR switch on the AF-P lens, VR is always enabled on these cameras since there is no electrical contact in the camera body to control it. (The AF-P version has 8 contacts compared to 7 on the AF-S.) But this incompatibility is almost certainly due to a business decision for planned obsolescence. There would not appear to be any reason why an AF-P lens could not have been designed to look like an AF-S lens as far the the autofocus commands are concerned. Or at worst, with a way of selecting the mode via a switch

    The AF-P 18-55mm lens is also significantly narrower than the AF-S VR lens and very slightly narrower than the AF-S VR II lens which could be in part due to the more compact drive setup. The piezo motor has a relatively large diameter (almost 1/2 inch) and the gear train also takes up space. For smaller lenses like these, the only option is to increase its overall diameter. The stepper motor with its direct worm drive can greatly reduce the required space.

    Most problems with these AF-P lenses fall into 2 categories:

    • Users don't realize that AF-P lenses will not focus (either auto or manual on older DSLRs as noted above including cameras prior to the D5300 and D3300. They are partially compatible with some like the D5200 if the latest firmware is installed. Check the on-line Nikon compatibility chart for your camera(s). A Web search will find one.

    • The Lock mechanism gets abused mostly attempting to rotate the Zoom ring from the locked (retracted) position without depressing the Lock button. There is only a small plastic ridge that prevents movement and eventually (or sooner) it wears or breaks. It's almost inevitable with this lens. However, the lack of Lock from the locked position can be considered more of a feature than a fault or bug as it won't restrict your ability to get the lens shooting. Lock is really only a benefit for long lenses which may creep. This short lightweight lens does not creep. ;-) (However, failure of Lock going the other way - from 18mm to Locked - can be annoying as the camera will not do anything useful in that area and will drop out of "Live View" if it was in that mode.)

    The AF-P lens destined for analysis is definitely well worn. The lock button doesn't work properly and in addition, one of the three tabs on the bayonet mount is broken off. Nonetheless, it still seemed to work well enough on a camera. But from the start, its days were numbered. ;-)

    After starting the dissection, I had other suggestions for the "P" in AF-P: "Pathetic" or perhaps "Plastic". Nearly everything structural is made of plastic except the screws, some specer rings/shims, and a few tiny brackets. The sleeve/barrel that "programs" the motion of the lens groups based on the zoom setting is a polished anodized aluminum cylinder with precision milled slots in the AF-S VR lens (and most likely the ED lenses that came before it). But it is made of plastic in the AF-P lens, though this change actually occurred with the AF-S VR II lens.

    However, having said that, the AF-P lens is much simpler and may be more reliable than its AF-S cousin. Autofocus has only two moving parts - a stepper motor with worm gear shaft which moves an internal lens group over a total distance of around 7 mm using low voltage drive. Compare that to reduction gears in the AF-S lenses along with the possibly tempermental ultrasonic piezo motor. The manual focus ring generates signals to the microbrain that then controls the same motor - it is not directly coupled to it: "Focus by Wire". Vibration Reduction (VR) is simplified as well with no Hall-effect sensors or lock mechanism. As a result, the electronics are also much less complex. In fact, as will be seen below, the electronics is perhaps an order of magnitude simpler in terms of the number parts compared to the AF-S version. This may be largely due to the lack of need for the high voltage piezo drive since the large ferrite inductors or transformers and drive components are eliminated. But may also be due in part to the higher level of integration available at the time of its design. And there are no critical surfaces to get contaminated as with the ultrasonic piezo motor. So I officiatlly retract "Pathetic" because the AF-P lens should be functionally at least as capable as the AF-S version, and more reliable without the SWM, high voltage drive, and gear train.

    But it almost appears as though this particular lens must be assembled from the inside-out. :( ;-) For example, in order to get to access any internal parts, the curved strip with contacts that make connections to the camera body must be disassembled down to its individual contacts, which then pop out all over the place. It isn't self contained with the flex-cable as in the AF-S. So if the plastic bayonet mount gets damaged (as would seem to be quite common even though this is a small light-weight lens), replacing it requires some serious manual dexterity. Nikon must have saved 3 cents. ;-)

    Taking it to bits non-destructively isn't that bad, though putting it back together without detailed instructions would be like solving a 10-level Rubik's Cube blindfolded. ;-) But that may be resolved soon.

    One mystery is solved though with respect to the silent propulsion system for autofocus. As expected and noted above, there is a very small stepper motor (~3/8" diameter) whose shaft has an integral worm gear and no other gears. That rests in a Nylon U-shaped bushing enabling the entire focus assembly with the 3rd lens group to be moved back and forth by around 7 mm with an opto-interrupter as a limit sensor at one end. The focus ring works in parallel with the manual focus electronically: There is an incremental encoder consisting of spokes on the perimeter of the focus ring with a pair of nearly microscopic opto-interrupters in quadrature to sense their movement. So, the stepper motor can be driven either by the autofocus electronics or focus ring essentially at the same time. It's "Focus by Wire". ;-) But manual focus will not work if power is off, which is only of academic interest unless the lens is used in an incompatible camera or for another application. This is fundametally unlike the AF-S version of this lens where the focus ring actually moves a lens group on a helical track and the A/M focus switch selects (1) whether it is coupled to the gear train and (2) lets the microbrain know.

    Without a gear train, this should be quieter than the AF-S. The stepper motor itself may make a detectable sound but sliding noise will reduced and there is no gear train to whine. But as a practical matter, the noise level of neither of these lenses is objectionable and only of relevance for some very specific applications where a "Do Not Disturb" sign is present. ;-)

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Optics

    The AF-P has 6 lens groups (unlike the AF-S that has only 4), though some may be single lens elements.

    • 1st lens group: Visible from the front, largest, fixed.
    • 2nd lens group: Vibration reduction, on 2-axis voice coil actuators.
    • 3rd lens group: Focus, movable by about 7 mm along optical axis relative to the others by the stepper motor.
    • 4th lens group: In front of aperture.
    • Iris diaphragm: Main aperture operated from camera.
    • 5th lens group: Behind aperture.
    • 6th lens group: Furthest back. This is the only one that can be adjusted in lateral position before tightening its screws and in theory will require alignment if removed.

    The position of the 1st and 2nd-6th (in the same relative position) lens groups move independently depending on zoom setting. The position of the 3rd changes relative to the others depending on focus setting controlled by the stepper motor.

    Most of the photos referenced below are also available as a Web Album (though possibly at slightly lower resolution) at Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Parts Web Album.

    • Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens - Complete Lens and Parts shows an intact lens at the upper left and most of the pieces that go into it. Of note are the miniature stepper motor (bottom left of center attached to the flex cable), the VR dual gyro flex PCB, the VR assembly and its cover (lower right of center), and the electronics PCB next to it.

    • Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Fixed Barrel with Zoom Encoder is a closeup of the encoder used to track the position of the 2nd-6th lens group. While the 1st lens group moves in and back out as the the Zoom Barrel is rotated from 55 to 18 mm, the 2nd-6th lens group moves unidirectionally from front to back. This movement may be observed from the rear on an intact lens as the Zoom Barrel is rotated. And as can be seen in the photo, the zoom encoder strip also runs from front-to-back along the inside of the fixed lens barrel, not around its outside perimeter as in the AF-S DX 18-55mm lenses. It's possible this was necessitated in part by the lock mechanism, which would otherwise have required an extended encoder strip with nothing on it. That might seem kind of silly, but could be used to indicate when the lens is unlocked. ;-)

      An absolute encoder for focus is not needed since the stepper motor is digitally precise: The position of the 3rd lens group for focus is proportional to the number of steps and direction referenced to a limit sensor at startup. The focus ring at the front of the lens is incremental and does not control the focus setting directly.

    • Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens - Autofocus and Vibration Reduction Electronics Printed Circuit Board shows most of the smarts. There are just a few small components on the bottom of the PCB. Compared to the AF-S, this is much much simpler.

    • Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens - Stepper Motor with Worm Gear and Focus Lens Coupling is a closeup of the miniature stepper motor (around 3/8 inch body diameter) more-or-less in the relationship it has in the lens. Though, the thing may be reversed end-to-end, live with it. ;-) The worm gear simply sits within the Nylon cradle. It has no premade teeth or grooves. That motion should be very quiet.

    • Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens - Main Aperture Parts shows what happens if care isn't taken when the aperture is exposed by removing the 5th lens group mount above it. If the aperture is moved past the normally minimal size position, there is only a weak detent (the hib sticking out of the left side of the Aperture Rotor) to prevent it from not being retained and then everything can fall apart. This cannot happen when the 5th lens group mount is installed. More below.

    • Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens - Vibration Reduction Assembly shows the top and bottom. Note how much simpler this is compared to the AF-S version. The Hall devices are also gone, so their funtion must be accomplished in some other way. The 3 suspension springs are readily visible along with the elastomer goo blobs underneath. ;-) Together, they do a good job of keeping the lens fairly well centered regardless of the orientation of the overall AF-P lens. It's not perfect but doesn't need to be.

    • Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens - Vibration Reduction Epson V7001B MEMS Gyros (Unfolded) are a different model with digital output but similer in function to the ones in the AF-S. They are on a flex-cable that is folded when installed so they would be at right angles to each-other.

    Here is a summary of the Nikkor 18-55mm AF-P DX f/3.5-5.6G VR lenses I've acquired so far

    Nikkor 18-55mm AF-P DX f/3.5-5.6G VR Lenses:

    • ID #1 (SN: 24105203): The lens that came with my D5600. Sold with the camera...

    • ID #2 (SN: None): The well worn lens was used for the original disassembly but without enough attention to detail to call it a dissection. This only had a non-working lock button and a slightly broken bayonet mount. (There is a small piece missing near the aperture lever, but that didn't noticeably affect the stability of the mounting.) It did take pictures. There is no SN but I don't know if it fell off or was missing from the start. I should not have taken it to bits but waited for a certifiably dead AF-P lens with good bayonet mount to transplant. Reassembly is not going to happen for this one. Oh well. Its bayonet mount was used for a noble purpose though - to somewhat repair ID #22 and then to #33 for safe keeping as that lens is dead.

    • ID #3 (SN: 22091057): Lock doesn't work but otherwise functional...

    • ID #4 (SN: 21672615): Fully funtional...

    • ID #5 (SN: 24816754): Lock doesn't work but otherwise functional..

    • ID #6 (SN: 20566871): Lock doesn't work but otherwise functional...

    • ID #7 (SN: 23321760): Fully functional placed in original box from AF-P #5.

    • ID #8 (SN: 21209477): Filter ring has damaged edge and there is a small scratch on front of 1st Lens Group. Replaced both with parts from ID #2...

    • ID #9 (SN: 24087896): Excellent to new condition.

    • ID #10 (SN: 20409376): Excellent condition except Lock doesn't work...

    • ID #11 (SN: 23250379): Excellent condition except for scratches on outside of front lens group. Swapped with front lens group from #2 but there is also a small scratch on that one. ;-(

    • ID #12 (SN: 25072941): Excellent to new condition. The seller description included something along the lines of "returned because not recognized by camera". I messaged the seller about the AF-P lenses not working with older Nikon DSLRs but they didn't want to bother retesting it. My conscience is clear.. ;-)

    • ID #14 (SN: 866178): Excellent to new condition cosmetically. A few scuffs on the front lens surface which would probably have little to no effect on picture quality. The seller listed as "For parts or not Working". I told them about these not be compatible with older camers. They tested it with a D90, nope. I offered to cancel they said it was OK. I didn't press it though... ;-)

    • ID #15 (SN: 23909452): Excellent to new condition cosmetically and functionally. Another case of tested on an incompatible camera, a D7000. It would seem like a higher model number camera would be compatible but no. The seller was notified and took it in stride. I only feel slightly guilty... ;-)

    • ID #16 (SN: 21013293): Very good to excellent cosmetic condition and perfect functional condition. AF and VR tested...

    • ID #17 (SN: 22484413): Very good to excellent cosmetic condition and perfect functional condition. AF and VR tested...

      ID #18 (SN: 22251593): Very good to excellent cosmetic condition, perfect functional condition. AF and VR tested...

    • ID #19 (SN: 22614685): Very good to excellent cosmetic condition, perfect functional condition. AF and VR tested...

    • ID #20 (SN: 21758842): Very good to excellent cosmetic condition, perfect functional condition. AF and VR tested...

    • ID #21 (SN: 20400885): Very good cosmetic condition and perfect functional condition except that Lock does not work at all, either from the storage position or to limit Zoom within 18-55mm...

    • ID #22 (SN: 21582536): Well used cosmetic condition though there is no physical damage except that the bayonet mount wss destroyed. So it would not even mount on a camera, or at least will not stay in place. It's barely possible to test. The glass is pristine, Zoom is smooth, and AF and VR are fully functional, for whatever that's worth. Lock even worked perfectly! But a replacement bayonet mount costs more than this lens! ;-( So the slightly damaged bayonet mount from ID #2 was transplanted. Now it is fully functional and seems happy and secure. But then the #33 Back Shell which only lacks locking from the locked position became available so the Back Shells of #22 and #33 were swapped. But now the lens with this SN will not lock anywhere and is just the remains of the show-and-tell dissected #1 so I'm confused. ;( ;-) This is listed as #33..

    • ID #23 (SN: 21741836): Very good to excellent cosmetic condition, perfect functional condition. AF and VR tested...

    • ID #24 (SN: 24870020): Very good to excellent cosmetic condition, perfect functional condition. However, Lock doesn't engage reliably between the 18mm and locked position. There is a click but Zoom may continued beyond 18mm toward the Locked position. So it's possible to accidentally disable the lens when not expected. AF tested and VR tested. The Bayonet mount from lens #30 has been swapped so this lens is now fully functional. But it has the #31 SN (and will be listed that way). I'm not also swapping the SN label! #24BDY/#30BS. Mounted on D5600 #3.

    • ID #25 (SN: 21671163): Very good to excellent cosmetic condition, perfect functional condition, AF and VR tested...

    • ID #26 (SN: 21815774): Very good to excellent cosmetic condition, perfect functional condition except that (1) Lock from the locked position doesn't always lock and (2) there are two pieces missing from the Bayonet Mount so the lens is not secure. The Bayonet Mount was swapped in from #28 so the SN is actually #28's and it's not going to change. ;-) AF and VR tested...

    • ID #27 (SN: 21415226): Very good to excellent cosmetic condition, perfect functional condition except that Lock doesn't work at all and there must be a piece of something preventing Zoom beyond around 48 mm. AF tested VR needs to be tested. After removing the Rear Shell, nothing fell out even after gentle whacking and shaking. So it was put back together. Replacing the contact spring became a pain and threatened to jump off. A tiny bit of 5 Miiute Epoxy was used to secure the spring inside the contact to prevent that. The lens works again except for zoom only being 18-48mm with no locking anywhere. VR tested. Mounted on D5600 #4.

    • ID #28 (SN: 21209302): Very good to excellent cosmetic condition but the Aperture Tang and cradle are both broken. So aperture doesn't work and will not be easy to repair as the cradle is deep inside the lens. The Bayonet Shell was swapped into #26. The Manual Focus Retainer was swapped with #29. So this is a parts unit now stored in box with PCB from #33.

    • ID #29 (SN: 21404549): Very good to excellent cosmetic condition except for 2 almost invisible dings or just missing bits of AR coating on the front glass of no consequence, perfect functional condition, AF and VR tested. 1st lens cluster has been swapped with the one from #28..

    • ID #30 (SN: 22104081): Very good to excellent cosmetic condition, perfect functional condition except that Lock doesn't work from Locked position. "It's a feature, not a bug.". ;-) AF and VR tested...

    • ID #31 (SN: 23613513): Very good to excellent cosmetic condition and perfect functional condition except that the cage that secures the Manual Focus Ring Retainer has a broken lock piece and it and the ring do not stay in place when the Zoom Barrel is extended. Originally I thought that would require extensive disassembly to replace, but some careful jiggling while pulling of the good cage from lens #28 seemed to be effective with no apparent damage. So this lens may now be fully functional, though VR still needs to be tested...

      However, to be confident of reliability for resale, its Bayonet Mount was swapped with the one from lens #24 which could slip past the 18 mm end of the zoom range. So technically, this is now strictly speaking lens #24 except for the Back Shell with the #31 SN.. Confulsed yet? ;-)

    • ID #32 (SN: 25119125): very good to excellent cosmetic condition and perfect functional condition except that Lock doesn't lock from the locked position. It's a feature, not a bug. ;-) VR needs to be tested..

    • ID #33 (SN: 20601205): Very good to excellent cosmetic condition except for a fine scratch on the front glass but both A and M focus is dead and Lock doesn't lock from the locked position. The Back Shell has been swapped with the one in #22 so that lens is now fully functional. This one is still dead as far as focus is concerned. It is recognized the the camera but there is a delay before Live View (among other functions) will respond indicating difficulty in initialization. The camera does respond to the zoom setting by limiting the aperture accordingly. For what that's worth. ;-) The PCB from #28 installed. No change. So this is a probably a mechanical problem or bad focus motor preventing Focus from initializing. That is consistent with a delay is the camera allowing Live View. It's probably not able to confirm focus lock. This PCB now with the box of #28 parts. ;-) The #33 Back Shell / Bayonet Mount installed on #22. Listed as #33..

    • ID #34 (SN: 20887887): Very good to excellent cosmetic condition showing hardly any signs of use, except that Lock doesn't lock from the locked position, but that takes only one lapse of attention. However, focus does not initialize and both M and A focus are dead.

    • ID #35 (SN: 23588779): Very good to excellent cosmetic condition except for wear on the silver decorative strip, but Lock doesn't work reliably anywhere. AF tested, VR needs testing. Mounted on D5600 #2.

    • ID #36 (SN: 21401647): Very good to excellent cosmetic condition, perfect functional condition. AF tested, VR needs testing...

    • ID #37 (SN: 21403550): Very good to excellent cosmetic condition, perfect functional condition. AF tested, VR needs testing...

    • ID #38 (SN: 22672146): Very good to excellent cosmetic condition except that Bayonet Mount is shreaded, functional condition TBD.

    ID #13 was skipped for no justifiable reason. ;-)

    Non-VR Nikkor 18-55mm AF-P DX f/3.5-5.6G Lenses:

    • ID #1 (SN: 20439915): Very good to excellent cosmetic condition, appears to be in perfect functional condition, AF tested. I did not realize this didn't have VR until it was tested and VR didn't work. Then I looked at the label...

    • ID #2 (SN: 20343955): Very good to excellent cosmetic condition, appears to be in perfect functional condition, AF tested...

    Finding a certifiably broken (defined as totoally non-functional, not even recognized as a lens by the camera) AF-P lens has been a challenge. Sometimes it's a case of the seller testing using an incompatible camera or not realizing the lens won't be recognized if locked. I usually attempt to inform sellers of these possibilities. Really. I haven't gone so far as to ask for a refund because the lens works though and there is ample information available about compatibility including here. ;-) As can be seen, the lock doesn't lock on some of these. Can you say "poor design"? ;-) There is a plastic ridge on the inside of the zoom barrel and gets damaged if attempting to rotate it without pressing the lock button. Or something. So that doesn't qualify as "broken" and can be claimed as a feature, not a bug, as rotating out of the locked position doesn't slow down shooting. And LOCK is pretty irrelevant on these short lenses that don't creep. ;-)

    There are currently 2 parts-unit lenses: #2 which was totally discombobulated for the original dissection photos with no hope of restoration, and #28 which now has bit of #26 and #29. Both of these appear to have good PCBs but with mechanical issues.

    Problems with AF-P DX 18-55mm f/1:3.5-5.6G lenses based on the list above (excluding just plain wear or abuse):

    1. Lock issues are by far the most common problem, which is unique among all common lenses as this is the only one with such a cheezy Lock implementation. Lock not being reliable from the Locked position is most frequent, which turns out to be a feature, not a bug since it's not needed and just increases the time to get shooting! The other case - not being restricted to the active Zoom range is less common. That can be annoying at the very least as moving Zoom beyond 18mm will result in the camera dropping out of Live View if it was active and disabling the shutter. There is also one instance where a plastic bit that probably broke off as part of the Lock mechanism was stuck deep in the lens resulting in Zoom not quite being able to reach 55mm. Approximately 1/3rd of the 18-55mm lenses tested had Lock issues. And around 1/3rd of those didn't restrict Zoom to 18-55mm. A few had both.

    2. Next up would be a broken Bayonet Mount (which is combined with the Back Shell for this lens and the AF-P DX 70-300mm, but NOT the AF-P DX 10-20mm or AF-P FX 70-300mm). Sometimes this is just cosmetic but could result in insecure or wobbly attachment to the camera. This is usually a result of an overzealous attempt at mounting the lens to the camera when it isn't properly seated.

    3. Followed by broken parts in the aperture mechanism - the plastic tang that is moved by the camera via the metal lever, or less commonly the cradle in which it rests. Depending on the break is, the aperture lever will have no effect on the iris over part or all of the Zoom range. It's not clear how this happens only on some lenses. In principle repair may be possible after a fashion these using some thin sheet metal and adhesive, though that could get tricky. Where the plastic tang is broken into 2 or more parts, adhesive will not hold up.

    4. Out of the 35+ of these I've seen, none were totally dead but at least 2 had non-working focus which for all intents and purposes is just as bad since even manual focus will not work.

    Replacement Back Shell / Bayonet mounts which should remedy issues #1 and #2 are available for $25-30. They do not include the aperture ring so do not help with issue #3. These are almost certainly Far East knock-offs. I have not yet tested one so do not know how well they work either functionally or cosmetically. They have a facsimile AF-P DX 18-55mm label but no VR on it.

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Disassembly

    Not all of the following is needed depending on whether this is for repair or curiosity. Specifically, to replace the plastic bayonet mount requires a much simpler and lower risk procedure. See the section below.

    Do NOT disassemble this (or any similar lens) if the future of the Universe depends on getting the thing back together in a functioning condition. At lest not if it's your first (or tenth) one. ;-)

    • Peel off the name label on the front. This can be done by sliding a business card under it from the lens element edge and lifting, then peeling it off entirely. Do NOT use anything that might scratch the glass (should you care).

    • Remove the 3 screws securing the Filter Ring.

    • Mark the orientation of the front (1st Lens Cluster) so that it can be replaced with the same orientation. This probably doesn't matter for this lens but won't hurt.

    • Remove the 3 screws securing the 1st Lens Cluster. The primary reason to do this first is to be able remove it from harms-way so it won't get dirty or damaged. If there are any circular shims under it, set them aside with it. There are probably none.

    • Remove the 3 screws securing the Rear Cover Ring and lift it free. The 8 ball contacts can now be picked off one at a time but two more steps and they will all fall out, which is simpler as long as it is expected. ;-)

    • Set Zoom to the 55mm position. This retracts the rear lens group so it is safely inside the lens.

    • Remove the single screw securing the Contact Retainer. The contact assembly will separate into two parts. The contacts can now be removed simply by turning the lens upside-down on a padded surface.

      (Of all the common Nikkor CPU lenses I've dealt with, only AF-P lenses are constructed like this. On AF-S lenses, the contacts and flex-cable are a self-contained assembly attached via 2 screws. The AF-P scheme really isn't a problem as long as the free contacts are expected. Inserting them during reassembly is simple enough.)

    • Gently maneuver the contact housing with flex cable so that it is free toward the center of the lens.

    • Unplug the flex cable attaching the ball contact assembly to the PCB. It pulls out toward the periphery of the PCB. Being able to do this may require the use of a custom "tool" to be able to grab it through the center hole. DO NOT pull up on the cable as that may break the connector. If only the Back Shell is being replaced, this flex cable can be left in place.

    • Remove the 3 screws securing the Bayonet Mount with Back Shell and carefully slide it off. Take care not to loose the tiny spring that is behind the ground contact. More on this below under "Zoom Lens Bayonet Mount Transplant". The ball contact flex cable can now be removed if it wasn't already.

    • Remove the remaining 3 cables connected to the electronics PCB. Two of them pull straight out. There are notches on the sides or a hole in the center to help with this. They do not have a latch. On the 4th, narrow black latch must be popped to the up position so the cable can easily be pulled out.

    • Remove the 3 screws securing the electronics PCB.

    • Remove the PCB by carefully angling it to avoid damaging the small plastic catch that seems to be there simply to make it difficult to get the PCB out without damaging it. ;-) Actually, it keeps the Ground Contact in place.

    • The lateral position of the 6th lens group may be critical so do the following ONLY if there is no desire to use this lens again (or you don't care about the quality of the photos it takes!) as alignment requiring specialized equipment and software would have to be performed to meet original specifications. However, if closup photos are taken of its precise original position showing how all 3 clearance holes line up with respect to the tapped screw holes and sealer, returning it there is probably sufficient for goverment work. ;-)

      Remove the 3 screws securing the 6th lens group and set it aside along with the screws and washers.

    • Remove the 3 screws around the perimeter. This should enable the entire inner assembly to slide out. Take care to peel the flex cable from the outer barrel so it doesn't tear or damage the spring contacts.

    • Squeeze together the 3 plastic tabs on the focus ring so it can be removed.

    • Slide out the inner barrel. This has the 2nd lens group (VR), 3rd lens group (focus), 4th lens group, iris diaphragm, and 5th lens group.

    • Unplug the small flex cable going to the stepper motor assembly. The black tab pops up on this connector to release it. Then peel the rest of the long flex cable off the barrel, which will also reveal the focus limit optical interrupter.

    • Remove the 2 screws securing the stepper motor and angle it out of the white Nylon cradle. The entire stepper motor wiring harness will now be free.

    • The dual gyros for VR are on a flex PCB glued to a compartment inside the inner barrel. Remove these for study only. ;-) Carefully scraping off the glue and peeling the PCBs from the plastic will free everything. Else leave well enough alone.

    • The iris diaphragm (main lens aperture) is on the back of the inner barrel DO NOT DISASSEMBLE. Once the inner barrel removed, doing so accidentally is all too easy bacause there is only a weak detent to prevent the iris actuator disk from being rotated beyond the inner stop. If this occurs, the entire thing falls apart and the leaves and tiny spring go flying. (The AF-S iris is a self-contained unit so this issue doesn't exist for that lens.) Without a jig of some sort to keep everything in place, it's virtually impossible to reassemble it. Trust me, it was still sitting in pieces after an hour or more, with some close calls on parts flying off to never be found again. The leaves weigh next to nothing and one or more will pop out of place if anything is disturbed like a leaf in the vicinity and the last leaf to be installed tends to make things worse since it has to slip under the next one over. That's assuming they were all rounded up along with the tiny spring in the first place. :( :) It was finally reassembled successfully by preloading a pair of plastic tweezers with an elastic band so little force would be needed to grip the leaves, placing one after another in the fully open position, and then gently nudging each one to the almost closed position where the top plate could be dropped in place and rotated to lock it. Then the spring was installed making sure to always have one end secured so it couldn't go flying off. Doing this a second time would probably not be as traumatizing but I'm not going there. ;-) If nano robots don't do the assembly in the factory, there is probably a jig that holds the leaves in place as they are installed and positioned using vacuum pickup tool until the top is in place and secured. It would be truly fascinating to see the automated assembly line in action. Humans would go stark raving mad doing this repetitively.

    • The VR assembly is under the gray plastic sheet, which can be peeled off.

    • Remove 3 screws and gently push the VR assembly with the 2nd lens group up from the opposite side as it's on metal rods (yes there is some metal in this thing!) and doesn't just fall out like most other parts when their fastening screws are removed. The movable 3rd lens group used for autofocus is under the VR assembly on the same rods so now is a good time to remove it so it doesn't just fall out when least expected.

      The VR assembly is much simpler than on the AF-S lens. The Hall-effect position sensors are gone as is the lock mechanism. Three really tiny springs as well as two blobs of some elastomer goop hold the lens element more-or-less centered regardless of orientation. There are only two coils and their associated pairs of rare earth magnets, each with U-shaped pole pieces.

      With no lock to restrict the movement of the VR lens, when VR is OFF (on cameras that support that), the only ways of minimizing movement are to effectively short out the coils which will reduce movement due to eddy currents or for the VR system to drive the coils with appropriate anti-VR waveforms to effectively lock it in place. None of these would be available on cameras without an electronic VR-OFF setting. Or perhaps that elastomer goop serves a similar purpose. ;-)

    That's basically it. There are now a pile of parts where there used to be an AF-P lens. ;-)

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Resassembly

    Reassemble in reverse order, left as an exercise for the student or masochist. ;-) More to come.

    I have been able to reassemble it into a mechanically correct configuration, though that was a challenge. While it's reasonably straightforward to get the major pieces screwed into their proper place, fitting them into the appropriate combination of grooves and slots in the cylinders that control how far each one moves as a function of zoom is a challenge. There are probably match-marks in conjunction with jigs that to the trained (Nikon) eye would make this intuitively obvious. The parts now move in what appears to be the correct way based on zoom, but that was through random chance. There are 3 separate assemblies that move based on zoom that need to go into their respective grooves and slots, and also need to be correctly oriented with respect to the quasi-3-fold symmetry of the lens, so among other things, the zoom distance labels, and mark and lock line up correctly. This will become more straightforward with experience, but certainly is a challenge the first time.

    And having been successful with the AF-S VF II, I am optimistic that this one will yield to enough determination.

    The more I look at these, the more they appear to be marvels of engineering down to the casting/molding of the numerous circuitous groves, slots, holes, posts, blocks, and other structures in plastic. It's probably just Zoom Lens Design 101 but still impressive to the uninitiated. ;-) Unfortunately, sometimes they aren't strong enough as will be seen with the 18-70mm lens, below. :(

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Bayonet Mount Transplant

    The following also applies nearly word-for-word to transplanting the Bayonet Mount on the AF-P 70-300mm f/4.5-6.3G ED and VR lenses as the back-end construction is identical. The main difference is that tho Back Shell is slightly larger so they are NOT interchangeable. It's also close for the AF-P 10-20mm f/4.5-5.6G ED VR lens differing mainly in that the Back Shell and Bayonet Mount are separate pieces. That annoying grounding spring is present though for all. ;( ;-)

    Failure of the plastic bayonet mount on these lenses is quite common. It probably is more due to attempting to install the lens on a camera when it's not seated properly than from physical abuse while shooting. This AF-P 18-55mm and 70-300mm lenses appear to be unique in that the bayonet mount is part of the molded rear shell. And as noted above, the AF-P lenses are also unique in that the individual camera contacts are not secured in a separate assembly but will pop out as the back of the lens is disassembled. This in itself isn't terrible but it's important that none get lost. This transplant can be performed without unplugging the flex cable or going inside the lens. As always, do this on a padded surface with a lip so tiny screws and other parts cannot roll away.

    Replacing the bayonet mount will also cure most issues with Lock including not locking from the Lock position or not staying within the 18-55mm zoom range.

    The following assemes that the replacement Bayonet Mount is bare - without the Aperture Actuator Assembly.

    Disassembly

    1. Set Zoom to its maximum setting (55 or 300 mm as appropriate) to retract the Rear Lens Cluster inside the lens. Note: In the case of the 18-55mm lens, if there is damage to the locking mechanism, this may not be possible, so set as close as it will go. The 70-300mm lens has no locking meachanism.

    2. Remove the three screws securing the Rear Cover Ring. Remove the Rear Cover Ring and inspect it for damage, which isn't that likely as it's not what usually gets abused. Set it aside with its screws.

    3. The eight Camera Contacts should still be in place, weakly held there by their spring force. It's simplest and safest at this point to use something pointy to pull them out so they can be set aside on your terms, rather than jumping all over the place in the next step. Inspect them for damaged (like being squashed). But if they don't come out easily, proceed to the next step.

    4. Remove the single screw securing the Camera Contacts Housing with its flex cable, which will now come loose. (If the individual Camera Contacts were not removed in the previous step, they will all fall out now.) DO NOT detach the flex cable unless it is faulty. With care, it can stay in place throughout this procedure. It will generally be out of the way most of the time.

    5. Carefully remove the Rear Shell with Bayonet Mount from the lens lifting straight up. There is a single grounding contact having a ball-end with a spring behind it that pokes through the Rear Shell from the PCB. It should be secure in a tiny plastic cage. If nothing is to be done to the main body of the lens, it can be left alone and will stay in place. But if it seems like it might pop free or the cage affair is damaged, I suggest carefully removing it and setting the spring aside in a safe place since that one is extremely easy to lose, it could pop out at any time when least expected, and finding a replacement if a ""Parts" lens is not available could be challening. More on this below. If there was an issue with Lock, check for bits of plastic from the Lock mechanism hanging around the Rear Shell, but they may be stuck deep inside the lens. Gentle tapping and whacking with Zoom at various positions may help to dislodge them. ;-( If any don't want to come out and are not causing serious effects on operation, it may be best to leave them. Going deeper into these lenses is not fun.

    If the replacement Bayonet Mount was purchased new and not transferred from another similar lens, it probably does not come with the Aperture Actuator Assembly (long plastic tang, metal lever, and plastic ring with spring). So this will need to be transferred. The following may be the most fiddly of all the steps. ;( ;-)

    6. Take a closeup photo of the tiny Apeture Spring that provides the restoring force for the Aperture Actuator. I doubt that replacing the spring reversed or backwards matters but a record of its original state won't hurt. Detach the spring taking care that it doesn't escape to be lost forever and doesn't get stretched or deformed. An unbent metal paper clip may come in handy here, and then to replace it below. For reference, here is a closeup: Nikkor AF-P Lens Aperture Tang Spring in Situ.

    7. Take a photo of the metal Aperture Lever to record its exact position so it can be reinstalled in the same place.

    8. Remove the two screws securing the Aperture Lever and set them aside with it.

    9. Rotate the Aperture Actuator Ring clockwise until it can be freed from the Bayonet Housing from the inside.

    Reassembly

    1. Install the Aperture Actuator Ring in the Bayonet Housing. It only fits one way and should drop in easily from the inside of the Bayonet shell. It should rotate back and forth without any resistance.

    2. Install the Aperture Lever using its two screws but do NOT fully tighten them. The Aperture Lever being in place will prevent the Aperture Actuator Ring from popping out.

    3. Install the Aperture Spring. This is by far the trickiest of all the previous and subsequent steps except for the tinier spring that follows if it has been removed. ;( ;-) My approach is to hook it on the plastic peg that points toward the outside of the ring and then use a slightly hooked end of a small wire paper clip to pull the loop over the peg that points along the ring away from the other one. If that makes any sense! Keep a finger on the other end of the spring while doing this so if it slips, it won't go "twang" into a pile of debris on your workbench or floor or in your trashcan. Confirm smooth operation of the Aperture Actuator.

       (It may be possible and simpler to install the spring as part of Step 1 by slipping its ends on the two projections before rotating Aperture Actuator Ring into position.)

    4. Confirm that the single grounding ball contact with its spring is still in the ball cup, or replace it if not or it was removed above. This may be even more finicky than the other spring as this one is smaller and more easily lost, and there is nothing to keep it in place except a plastic partial. But I suggest using a tiny bit of 5 Minute Epoxy to secure one end of the spring to the inside bottom of the ball cup so that it can't jump out. Then slip that with its attached wire into the cage. In addition or in place of the Epoxy, fashion something with a hole the same size as the diameter of the ball contact and use that as a positioner - attempting to manipulate the contact assembly by hand is extremely fiddly. The tab with the wire soldered to it slips in the gap and then is positioned under the cage to the left of the gap; the tab clockwise from it and the one opposite that go under the cage, The other two tabs appear to only be present to prevent lateral movement. There is a closeup of this in the dissection.

       Do NOT be tempted to either leave the spring off or the entire ball cup assembly. While there should be a return path through one of the 8 Camera Contacts which will provide grounding when the lens is locked in place, it will NOT be present at times while installing or removing the lens. This probably doesn't matter if power to the camera is off (as it should be!). But if power is on, there could be instants where there is a DC voltage applied to the lens with no proper ground. Theoretically, such a condition can damage the digital circuitry in the lens. I don't know how likely it is or even if it is possible, but better to be safe than sorry even if it takes a bit longer.

    5. Install the Rear Shell with the Bayonet Mount and Aperture Actuator back onto the lens after aligning the index mark on the shell with the one on the front of the lens. Confirm that the ball contact pokes through its hole in the Bayonet Mount and that the Aperture Tang has engaged inside. Test for smooth operation over the entire range of the Aperture.

    6. Secure the Rear Shell with the three screws removed previously.

    7. Gently position the Camera Contacts Housing with its flex cable into its position and secure it with the single screw removed previously.

    8. Install the eight Camera Contacts by gently slipping them in place individually. If any seem to be too "flat", carefully spread them out a bit.

    9. Temporarily place the Rear Cover Ring in position and adjust the Aperture Lever (With its screws loose) so it just touches the edge when in the relaxed (aperture stopped down) position. Or that it matches the position in the photo taken above. Remove the Rear Cover Ring and tighten the Aperture Lever screws. Confirm that it hasn't moved, repeat if necessary. Secure the Rear Cover Ring with its three screws.

    10. Finally, for OSD types, use a thin blade to carefully lift up one end of the serial number sticker so it can be peeled off and transfered to the replacement Shell. Add a bit of adhesive if it doesn't stay in place securely. No one will know.

    That's it! This should be a wrap. ;-)

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Lock Button Issues

    The following also applies to the non-VR version of this lens.

    Many Nikon (mostly longer heavier) lenses have a Lock button to prevent "creep" from the collapsed Zoom setting. This is a useful feature for lenses like the AF-S 18-300mm f/1:3.5-5.6G ED VR but is silly on the small light-weight 18-55mm that cannot creep under any circumstances in any position. And with a large movement between Lock and 18mm (to be able to collapse the lens when not in use), the Lock button serves a second function - which is critical - to prevent inadvertent movement out of the valid 18-55mm Zoom range while shooting. This was probably nherited from the AF-S DX 18-55mm f/1:3.5-5.6G VR II lens, which has a similar Lock button. None of the other AF-P lenses has a Lock button, not even the relatively massive AF-P FX 70-30mm f/1:3.5-5.6E ED VR, which does have a tendency to creep. ;-) But few, if any, of the other Nikon F-mount zoom lenses are able to collapse for storage like the 18-55mm lenses. (Some of the Z-mount lenses do have this feature.)

    But the way Lock is implemented on the 18-55mm lens means it is destined to fail eventually. Larger lenses have a slide lock that engages a deep slot in the Zoom Barrel. The 18-55mm lens simply has a spring-loaded metal tab that engages a thin flimsy plastic projection only order of 0.5 mm high in the relatively soft plastic on the interior of the Back Shell / Bayonet Mount. So if grabbing the Zoom Barrel to start shooting from the stowed position without depressing the Lock button, a lot of stress is placed on the plastic piece and it will eventually fail to do its job. Just getting slightly smoothed down will be enough. Lock from the locked position then no long works reliably if at all. This is actually a desirable feature, not a bug ;-) because for a lens that doesn't creep, there is no need for the lens to lock in the collapsed position and it just slows down shooting. However, loss of Lock restricting Zoom to the valid range is a bad thing. And that can fail in the same way. Accidentally attempting to rotate the Zoom Barrel past 18mm (from larger focal lengths) will result in the camera thinking the lens has been removed and Live View will be disabled. That uses the same spring-loaded metal tab and a similar flimsy plastic projection. A repair of the plastic would appear to be quite challenging. Fortunately, replacements for the Back Shell / Bayonet Mount are available and the transplant is not difficult. See the previous section.

    The AF-P DX 18-55mm lens was introduced in the year 2016. Yet, as far as I am aware, this deficiency has yet to be addressed (and of course never will be). All it would take is an increase in the size of the projection or to embed a couple pieces of metal in the Back Shell that could withstand the abuse.

    Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Dissection

    Similar to the one for the AF-S VR II lens, Coming soon, maybe. But for now, there is a Web Album at Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Dissection Web Album with some stock photos and optical architecture and how the lens groups move with zoom.

    Comparison of Nikon AF-S DX 55-200mm Zoom Lenses

    These are a popular 2nd lens after the kit lens as they cover the long telephoto range from 55 to 200 mm (equivalent to approximately 83-300 mm for the full frame FX format). Given the weight of the 18-300 mm lenses, carrying around this pair makes a lot more sense unless one needs to instantly switch from wide angle to telephoto (or would like to go into arm wrestling). The 18-200 mm lenses are HEAVY. But one deficiency with 55-200mm lenses is that the closest focus distance is not so close - 0.95 to 1.1 meters depending on the specific version.

                Gener-   (1)     Auto-   Focus     Focus       Manual       Year
       Model    ation   Optics   Focus  Encoder  Tachometer    Focus     Introduced
    --------------------------------------------------------------------------------
     AF-S ED      1   2C/9G/13E   SWM     Yes     Magnetic   Mechanical   2005?
     AF-S VR     1.5  2C/11G/15E  SWM     Yes     Magnetic   Mechanical   2007?
     AF-S VR II   2   2C/9G/13E   SWM     Yes     Magnetic   Mechanical   2007?
    

    1. E: Lens Elements; G: Lens Groups; C: Lens Clusters. Lens Elements are individual optics which may be glass, Extremely low Dispersion (ED) glass, or plastic, and may be normal (spherical) or aspheric. Lens Groups may be a single Lens Element or a glued combination like an achromat. Lens Clusters are my terminalogy for the sets of Lens Groups that move when changing the zoom setting. There will also be a focus group which will be part of one of the lens clusters and moves with respect to it. See the specific lens architecture diagrams in the lens dissection Web Albums for details. A Web search for the specific model lens may also turn up more on the optical design.

    2. It is interesting that the VR II may be more similar to the ED than the VR, although it is not yet known if the actual lens elements are the same.

    A montage showing stock photos of all known versions of the 55-200mm lenses as of 2022 may be seen at: Nikon AF-S DX 55-200mm f/4.0-5.6 Zoom Lenses. These are from Nikon lens product or review pages (copyright © Nikon Corporation) scaled so the relative sizes are close to correct. What's remarkable is how much larger the VR version is compared to the others. And then with the VRII it seems they decided "never mind". ;-)

    More to come.

    Nikon AF-S DX 55-200mm f/4.0-5.6G ED Zoom Lens

    There is a repair manual on-line for this lens. Search for "Nikon AF-S DX Nikkor 55-200mm f4-5.6G ED Lens Factory Service Manual" (without the quotes). It's the first hit using Google.

    This is a basic lens without VR.

    I have had 3 of these:

    • ID #1 (SN: 2497262): Definitely well used and sometimes is hessitant to autofocus if not used for a while. Now has 1st lens group from ID #2.

    • ID #2 (SN: 3495658): Mottled contamination *between* lens elements in 1st Lens Group. Now has 1st Lens Group from ID #1.

    • ID #3 (SN: 2265382): Not sure where that came from.

    I am currently evaluating how well swapping of the 1st Lens Groups on these lenses work without adjustments. There are the normal shims between the lens group and focus ring whose main purpose is to fine-tune the position of the 1st Lens Group so the lens can focus correctly at infinity. But #1 also had a pair of half shims on one side apparently to tilt the lens group slightly. It's not clear if that is a lens group issue, or lens focus ring or body issue. Can you say "kludge"? ;-) Considering how much free play there is in all these plastic lenses, it's not clear how much that would help. But perhaps #1 was a particularly bad specimen.

    Stay tuned.

    Removing the 1st Lens Group in the Nikon AF-S DX 55-200mm f/4.0-5.6G ED Zoom Lens

    The repair manual doesn't seem to even address this, but only deals with the removal and replacement of the entire front assembly. However, it turns out that the 1st Lens Group consists of a pair of lens elements mounted together in a housing which unscrews counter-clockwise. This was indicated by the pair of tiny holes for a spanner wrench revealed once the label was removed. But it turns out that this isn't even necessary. There are at least two ways to proceed. For both, first switch to manual focus and adjust focus and zoom so everything is fully extended. Grip the lens by the filter mount to minimize stress on the internal parts of the lens:
    1. Carefully peel off the label by slipping a thin stiff piece of plastic under it to lift one edge. Then go around the perimeter with a round wooden toothpick to free it. Alternative "tools" may be used. ;-) This is somewhat risky and there is a good chance the label will be damaged cosmetically in the process.

       With the label removed, a pair of holes for a spanner wrench will be visible, which is probably what Nikon uses since they have plenty of labels. ;-) Using a spanner is less stressful on the lens than #2 below. And it has the benefit that the label can be replaced in the original orientation. While the label would line up correctly if replacing it in the lens but not if swapping them between lenses. (A pair of tiny depressions for a spanner could also be drilled through the label 180 degrees apart no more than 1 mm or so in depth in locations avoiding the printing. The label would not need to be rmeoved and the cosemtic damage would be minimal.)

    2. An alternative which doesn't require removing or damaging the label uses a home-built "tool" consisting of a piece of 1-1/2 inch ID PVC pipe or coupling and double-sided tape or rubber glued to its end. Confirm that the end is flat - sand or file it flat if not. The PVC pipe fits the outer perimeter where the label is located perfectly and the sticky tape or rubber provides enough grip that it should be possible to then unscrew the 1st Lens Group. Apply just enough force so the adhesive or rubber does its job. Too much will just increase the required torque. And as noted above, hold the lens by the filter ring / lens barrel.

       This approach is also shown in Nikkor 55-200 : Haze and fungus removal - YouTube, though his lens appears to have been previously repaired.

    Once the 1st Lens Group is free, keep track of the shims. Should there be a partial shim or shims, it or they are probably stuck in place with some sort of adhesive and remain there unless the 1st Lens Group is being swapped with one from another lens or vice-versa. In that case, you're on your own. ;( ;-)

    Reassemble so it is just snug.

    Cleaning Inside the 1st Lens Group in the Nikon AF-S DX 55-200mm f/4.0-5.6G ED Zoom Lens

    For some reason, the inner surface of one or both of the elements in the 1st Lens Group seem to be what get contaminated, not the surfaces that are readily accessible by simply removing it.

    However, accessing them isn't too involved.

    1. Remove the 1st Lens Group taking care not to lose the shims as described above.

    2. The 2nd Lens Element at the back of the 1st Lens Group is held in place by a ridge of plastic a fraction of a mm across rolled over its edge. Use a fine file to *carefully* remove only the ridge going around its perimeter until the glass edge of the lens element is exposed. Take it slow to avoid damage to the edge of the fragile glass lens element. A single edge razor blade or something similar may be helpful to peel off the remaining sliver of plastic.

    3. Using a calibrated finger nail ;-) or similar tool, chip off a tiny piece of the remaining plastic so that the edge of the lens element is exposed.

    4. Put match marks on the glass lens element and mount so it can be replaced with the same orientation. Perhaps not necessary but won't hurt.

    5. It should now be possible to pop the glass lens element off without damage while retaining the mounting structure so that it can be replaced with the original alignment.

    6. Clean the now exposed inner surfaces of the lens elements with soap and water, lens cleaning fluid, hydrogen peroxide, and/or alcohol. The use of anything stronger is probably not recommended for the 1st Lens Element still in the plastic mount, which could be damaged. Acetone can be used for the other one, but typically that's not needed.

    7. Touch up the edge of the 2nd Lens Element with a black Sharpie™ or something similar if needed.

    8. Pop the 2nd Lens Element back into position with the match marks aligned making sure it's seated on the ridge. Add a few bits of 5 minute Epoxy or similar adhesive around the perimeter to assure it stays there.

    9. Reinstall the 1st Lens Group as described in the previous section, above.

    Just don't get over zealous in removing the 2nd Lens Element as I did and chip the edge, which could impact photo quality at low f/ stops. At the very least, it's ugly. ;(

    Nikon AF-S DX 55-200mm f/4.0-5.6G VR Zoom Lens

    I have not found a repair manual or even an exploded diagram for this lens. It is quite different than the original ED version or the VR II succesor in external construction and possibly optical architecture. If anyone has one for this lens, please contact me via the Sci.Electronics.Repair FAQ Email Links Page.

    I have four samples of this lens:

    • ID #1 (SN: 527838):This lens is not quite able to autofocus - it requires help but appears to try moving in the correct direction. After an extended period of attempting it, the bottom appeared to be getting warm.

      At first I assumed that the SWM itself was gummed up and unable to move. But the problem turned out to be that one of phases of the SWM drive signal was not present. Phase A (arbitrary designation) was nice and strong at around 240 V p-p but Phase B was dead. This was determined with the use of my 55-200mm VR SWM Test Rig, which does away with the Fixed Shell and brings out the two SWM drive phase signals and ground soldered to conveniently located pads on the SWM flex cable. So these and others can be probed in situ while on a camera. See the dissection photos for the actual contraption, as well as what the phase signals look like. There was also something strange about this lens as the grounding wire to the spring contact was disconnected at the contact-end and the insulation over most of its length was missing and the conductors were frazzled looking like a horses tail. ;-( It was replaced with the light gray wire in the photo. Whether that was the cause or result of the bad SWM drive - or a total coincidence - is not known. Testing the SMT transistors marked K1YSD next to the ferrite components with a DMM reveals that there is a short across a pair of leads for the lower one. According to an SMD marking code database, these are Samsung KSA3265-Y SOT-23 NPN transistors: 30 V, 800 mA, 200 mW, which would sounds about right EXCEPT that this is on the OUTPUT side of the transformer which can have more than 200 V on it! So perhaps it isn't a KSA3265-Y. Since I don't believe in coincidences, I wonder if the stray ground wire shorted to something and blew the transistor. But assuming the part number is correct, the Fairchild/ON Semi KSC3265 appears to be an acceptable substitute. Now to justify a Digikey order for a 26 cent part. ;-)

      As it turned out, the apparently shorted transistor was a red herring. These are not bipolar transistors but MOSFETs based on the Nikon patents. And stray voltage on the gate was fooling the multimeter into thinking there was a short. When that was discharged, the SO23 parts on both POW PCBs behaved the same.

      But swapping the POW PCB made no difference. One phase was still dead. The next step was to check the SWM. The dead phase was an almost dead short at the SWM. But swapping the SWM also made no difference. As a last resort, the CPU PCB was swapped and three was the charm. ;-) With the good SWM, original POW PCB, and swapped CPU PCB, the lens sprang to life. Autofocus now works. About those coincidences, it's possible I blew the original CPU PCB because the cable between it and the POW PCB was installed slightly angled and perhaps making improper contact when the POW PCB was first swapped. That causing the same problem is unlikely but if not, one must accept that both the SWM and CPU PCB were bad. VR doesn't appear to activate though even with the VR switch ON. Oh well, can't have everything.

      With the brain transplant, any parameters stored in its memory that were optimized for the lens from which the CPU PCB originated are now incorrect. How much difference that may make in real life is yet to be determined.

      This is now my "Visible" lens with its innards exposed. ;-) Even if it can be repaired, it may never be destined to be buttoned up. Having a partially naked lens could prove handy. ;-)

      An attempt was made to locate the short but it provded to be very well disguised even after complete disassembly of the SWM and under high magnification. So when subtlety doesn't work, try brute force: Discharging a capacitor across the "short" cleared it But nothing exploded, so its location is still a mystery. The SWM may get tested eventually. It was disassembled for the photo shoot, cleaned, and put back together.

    • ID #2 (SN: 896820):This one was stuck at 55 mm. The zoom bareel moved slightly but hit a hard stop. The alignment of the Back Shell and Zoom Ring was offset very slightly, which provided a clue.

      In fact, the cause turned out to be a crack in the Fixed Shell with a small piece hitting a spring pressure strip and getting stuck. Repair of a small plastic piece is not realistic so it was removed along with the metal strip, whose function appears to be to add some resistance so zoom doesn't move so easily that the lens changes the zoom setting on its own. However, with that done the lens appears to work just fine, thank you. Exactly how that Fixed Shell cracked is not at all clear. There is no sign of trauma to the lens. The Fixed Shell minus the offending piece is shown in the dissection. It is at the upper right of the Fixed_Shell_Front1 photo.

      AF and VR seem OK now.

    • ID #3 (SN: 3263342):Autofocus hunts and doesn't lock. Unless the problem turns out to be something trivial like a flex cable that became unplugged, the plan is to use the SWM and possibly the SWM PCB from this lens to repair ID #1. It appears as though transplanting the SWM is simply a matter of 4 screws and one plug-in flex cable. Of course, getting inside to access the SWM is a real treat, but after the third time should not be that bad.

      Initial finding on ID #3 is that the zoom value returned by the Zoom Encoder was incorrect beyond around 100 mm - 105 mm read back as 100 mm, 135 mm read back as 100 mm, and 200 mm read back as 145 mm. These data were determined from the EXIF data for a series of test shots. One common cause is contamination on the encoder strip. Unfortunately (or fortunately) depending on one's point of view, this appears to have corrected itself temporarily at least. Perhaps the contamination was rubbed off. This may be wishful thinking but for the time being it works so don't fix it. ;-)

      However, AF works well but VR doesn't seem to activate.

    • ID #4 (SN: 836632600): The back shell and its mounting posts are broken off, Camera Contacts cable torn, and Bayonet Mount broken. The SWM and CPU PCB were used to revive ID #1 so there may be no excuse not to use this for the detailed dissection. ;-)

    Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR Zoom Lens Description

    The 55-200mm VR lens is the largest and heaviest of the three which makes it much less desirable than the VR II version. It uses the typical SWM but with a fully enclosed gear train and a drive frequency of around 70 kHz based on measurements using a sense coil and scope.

    Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR Zoom Lens Disassembly

    This is only partial at present down to the level of exposing the SWM and PCBs.
    1. Remove the single screw securing the Switch Panel, swing it out revealing the interior of the Switch Bay, Unplug the flex cable by flipping up the locking level or by holding the connector with a pair of tweezers and pulling it out.

    2. Unsolder the thin grounding wire from the pad. Alternatively, cut the wire leaving enough at either end to strip solder during reassembly. Only if you do not have any way to solder should you consider unscrewing the grounding contact assembly from the Bayonet Mount which will be exposed when the Bayonet Mount is removed. It's almost impossible to get this back together without more hands than are standard equipment.

    3. Remove the 3 screws securing the Inner Ring and remove it.

    4. Remove the 2 screws securing the Camera Contact strip and gently push it toward the center of the lens so it is loose.

    5. Remove the 3 screws securing the Bayonet Mount. Lift it up and disengage the Aperture Tang from the prong on the iris diaphragm. Unlike most other lenses, this does not slip in place - the prong should bd lifted as far from the lens as it will go and then it should disengage. but it may be necessary to gently push the iris prong toward the center of the lens with a thin tool. This may require zoom to be set away from the 55 mm position.

    6. Add a small dab of 5 Minute Epoxy or something similar to the ground contact where the wire is soldered. Otherwise there's a good chance it will break off with even modest handling.

    7. There are anywhere from 1 to 4 or more shims under the Bayonet Mount. Label them as to orientation and top/bottom. If more there is more than one, also label their position in the stack though it really shouldn't matter. So arrange them with the thickest one on the back (top) which will make it easier to set them in place during reassembly. Sticking them together with adhesive in a way that doesn't change the overall thickness would also greatly simplify the fiddlyness of reassembly where more than one shim is present. A single wrap of thin Kapton tape away from any of the screw holes may be satisfactory. FWIW, ID #1 had a single thick shim while ID #2 had 4 - two thick and two thin. My guess is that a combination of binary thicknesses (i.e., 1, 2, 4, 8 units) of shims is selected during final testing to fine tune the optical location of the lens with respect to the camera body. Or something. ;-)

    8. Remove the Fixed Shell.

    At this point, everything that is simple to get at on the back of the lens is exposed.

    9. Remove the Rubber Grip by carefully lifting it along one edge and working it free of the Zoom Barrel.

    10. If it is desired to inspect the Zoom Encoder, peel off the tape securing the black cover sheet. It can be replaced with Kapton tape.

    More to come.

    Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR Zoom Lens Reassembly

    To use the lens on a camera without the Fixed Shell to inspect its innards or probe signals like the SWM drive, simply leave the Fixed Shell off during reassembly. The lens won't be quite as robust without it and high voltage (~240 VAC) will be present on some components and solder pads when focusing, but with care it should be perfectly satisfactory for testing at least. CAUTION: This stunt appears to be acceptable for the 55-200mm VR lens but may not be for some others where the closeup and/or telephoto zoom limits depend on stops on the interior of the Fixed Shell. For those, bad things may happen if rotated beyond them! ;-(

    Reassemble in reverse order. The most fiddly part of reassembly (after making sure the shipm stay in place) is probably reattaching the ground wire. If soldering back to the pad on the flex cable, cover the edges of the Switch Bay with Kapton tape or something similar to protect the plastic from accidental contact with the soldering iron tip. The wire was cut, stip the ends and solder them together, finally insulating with Kapton tape, plastic electrical tape, or a glob of 5 minute Epoxy. Coming someday.

    Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR Zoom Lens Dissection

    The start of a dissection is available at Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR Zoom Lens Dissection Web Album. So far it goes only as far as was required to repair ID #2 and described in the disassembly steps, above.

    More coming soon.

    Nikon AF-S DX 55-200mm f/4.0-5.6G VR II Zoom Lens

    I have not found a repair manual or even an exploded diagram for this lens. It appears more similar to the original ED version than the VR predecessor in external construction and possibly optical architecture, but with VR and the Lock button added. If anyone has one for this lens, please contact me via the Sci.Electronics.Repair FAQ Email Links Page.

    This is a rather nice relatively compact lightweight lens. It looks somewhat like an AF-S DX 18-55mm VR II lens on steroids and only very slightly larger than the 55-200mm ED version, both of which are shorter than the VR version.

    • ID #1 (SN: 20229424): Very good condition except that the Camera Contact strip was a bit pushed in on one end and the aperture prong didn't spring back as it should. While the lens was recognized by the camera, AF was dead. However, removing the inner ring and loosening and then readjusting the position of the Camera Contact strip seems to have cured everything. ;-) How that caused it to spring to life it not clear as the offset seemed very minor. But because the lens now works, it is not destined for dissection, only portraits, sorry. ;-)

    • ID #2 (SN: 20583677): The main problem appears to be that while the Lock button works for lock, the stop at the 55 mm-end is broken. So zooming in can easily overshoot. It is also somewhat tight which could be partly to blame for someone being overzealous and breaking the plastic stop. Or perhaps the broken bit is stuck inside somewhere clogging up the works.

    Since neither of these is really broken, the search is on for a third speciment for dissection and to repair ID #2.

    Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR II Zoom Lens Photos and Description

    The 55-200mm VR II lens is the most compact of the three which makes it much more desirable than the VR version. It uses the typical SWM and gear train but with a drive frequency of around 290 kHz based on measurements using a sense coil and scope. It also has the dither pulses continue for a few seconds after focusing like some of the other AF-S lenses.

    Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR II Zoom Lens Photos and Description

    The start of a dissection is available at Nikon AF-S DX Nikkor 55-200mm f/4.0-5.6G VR II Zoom Lens Dissection Web Album. But only stock photos, dimensions, a partial optical architecture diagram, and external photos.

    More coming soon.

    Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens

    There is a repair manual on-line. Search for "Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5 Zoom Lens Repair Manual" (without the quotes). It's the first hit using Google.

    Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens Description and Dissection

    This lens is interesting because autofocus uses a full diameter ring ultrasonic motor with no gears, which is why I bought it for dissection. These are called "Silent Wave Ring Motors", "Ring SWM", or for the geek types: Ultrasonic Piezo Silent Wave Ring Motors - or anything in between. Theoretically, they should be quieter, more reliable, and faster. But in reality, they may not be unequivocally any of these. The working sample I have is definitely not silent. And they are probably more expensive to manufacture even though there are fewer parts.

    Autofocus on this lens is quick, but not necessarily quieter than on the AF-S lenses using the small motor and gears. The motor and lens has sliding surfaces which still make some sound.

    • ID #1 (SN: US2748346): Decent cosmetic condition and fully functional.

    • ID #2 (SN: US3578427): Intact but will not focus at all because of broken prong on 2nd lens group housing. See below.

    • ID #3 (SN: Unknown): Partially disassembled with back shell and Bayonet mount parts missing. Reassembled with parts from ID #2 but there must be a problem with the zoom tachometer or encoder. It tends to oscillate around the correct focus but sometimes locks.

    But the sacrificial victim (ID #2) makes abnormally loud grinding noises and fails to be able to focus correctly - either manual or auto. :( ;-)

    The cause became obvious as a huge part - the entire 2nd lens group - was loose inside the lens not attached to anything just bouncing around. ;-( Figuring that the 1st lens group would detach like the others - by unscrewing it after removing the label, that was attempted first. But either it has left hand threads or it is really tight and I don't have the needed spanner wrench, so it remains securely attached. No matter. ;-)

    Plan B was to go in from the back, where the action is in any event. This turns out to be quite simple and even reversible. Removing several screws around the side of the bayonet mount and the back allows both to be removed without damaging anything. The electronics PCB is then exposed and its cables can be unplugged easily along with the Focus A/M switch revealing the full diameter autofocus Silent Wave Ring Motor. The contacts remain safely inside their housing.

    Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens Photos and Description

    Most of the photos referenced below are also available as a Web Album (though possibly at slightly lower resolution) at Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens Parts Web Album.

    Being simpler than the VR lenses, there are fewer photos for this one, but there is always the on-line repair manual to refer to:

    • Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens - Major Sub-assemblies from left to right: 1st lens group and front extensions, 2nd lens group, 3rd-5th lens groups and aperture, autofocus Silent Wave Ring Motor (SWRM), and back shell with bayonet mount and electrical contacts. Focusing is done using the 2nd lens group which fits in spiral grooves and is moved via the tab. That tab was found rattling around inside the lens broken off and in two pieces. Possibly the lens was dropped. It is now recemented for the photo shoot only. The tab is likely strong enough under normal use. Without the tab, the 2nd lens group was free to unravel entirely from its grooves and just bounce around inside when the front was extended. The Moire pattern in the 1st group photo is a result of the internal anti-glare grooves distorted by the lens elements.

      According to the repair manual, alignment will be required if the 4th or 5th lens groups are removed. So, avoid doing this if possible. Or, at least, as each of the 3 screws is removed, take a closeup of the exact relationship of the screw hole to the clearance hole.

    • Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens - Autofocus Electronics Printed Circuit Board shows both sides. The complexity of this is much greater than that of the AF-P lens, above. And that one also incorporates vibration reduction (which this lens lacks). Note that both large square ICs have a Nikon marking.

    • Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens - Ultrasonic Piezo Ring Motor (or Silent Wave Ring Motor). From left to right has how it appears in the lens, the motor parts stacked, and just the stator with the piezo elements sitting on the toothed rotor. The long curved strips are the two phases to set up the traveling wave clockwise or counterclockwise.

    • Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens - Ultrasonic Piezo Ring Motor Parts shows the active components separated. The black/silver ring is what actually moves on a set of rollers with ball bearings.

      Prior to disassembly, the piezo motor did work well when focusing, moving from one end to other in 1/10th of a second or less. However, due to the broken tab on the 2nd lens group cell, it didn't do anything useful. :(

      That gray spot where the flex cable center conductor attaches to the PZT stator ring (left-most piece in the left photo) almost looks burnt. But it's just a bit of conductive adhesive to assure good contact. There is a small hole in the flex-cable underneath it.

      The rotor (right-hand pieces in each of the photos) consists of 4 parts: The aluminum ring with a lip which is what's in contact with the stator, a thin steel ring next to it, a segmented aluminum ring next to that, and the black plastic shell molded around everything, The sliding surface of the rotor is an insulator, possibly an aluminum oxide coating, and there is also no electrical contact between the metal rings embedded in the plastic shell or to the rotor itself.

    • Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens - Closeup of Ultrasonic Piezo Ring Motor Stator and Rotor shows the details.

      To check the drive signal, a 3 turn coil was wrapped around the working AF-S 18-70mm lens. Not surprisingly, its frequency is much lower than for the small motor in the AF-S 18-55mm lens, clocking in at only around 28 kHz. The frequency is still ultrasonic, but not by that much. ;-) And as noted with respect to the AF-S 18-55mm lens, above, this would be a good way of determining if autofocus failure is due to lack of drive or a mechanical problem. But the sensed amplitude is lower, at around 20 mV p-p since the source is more buried. Use more turns if desired. ;-)

    This lens appears to be more repair-friendly than the ones above especially if there is no need to go inside the assembly with the 7th-13th lens groups. There should be no need to unsolder any wires and the flex cables detach easily. As noted above, just keep track of everything with photos, notes, and added match marks.

    However, note that there is a magnetic strip and magnetic pickup that provides a signal in place of the tachometer in some lenses that have the small SWM with gear train. Not only is it delicate and damaged easily, but ferrous tools can cause the magnetic pattern to become corrupted, which needless to say, would not be good. Even accidentally touching the strip with a slightly magnetic screw drive could potentially erase it.

    And if you're curious as to how the focus is controllable mechanically both via the Focus Ring and Ultrasonic Piezo SW Ring Motor at the same time, it's similar in concept to a differential gear box but with no gears. Focus is actually controlled by a ring with a metal fork that engages the plastic tab on the middle lens cluster. That is mounted on ball bearings as shown in the photo above. On the front-side is a plastic ring that is in contact with the ball bearings that engages with the rubber/plastic manual Focus Ring. On the back side is the rotor of the PRM which is in contact with the opposite sides of the ball bearings. The friction of the focus fork ring is quite low (or should be) so when the ball bearings are rotated by either the Focus Ring or Piezo motor rotor, it moves at 1/2 the rate of either but does not (or at least should not) affect the other ring. However, where the lubrication had gummed up or there is damage from abuse, movement can be inconsistent. This appears to be a common problem with the AF-S DX 18-200mm f/1:3.5-5.6G VR and VR II lenses (below) where focus fails to work properly over part of the Zoom range or at all.

    There are no immediate plans for a detailed dissection but for now see the Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens Dissection Web Album. There is no dissection yet but it shows some stock photos and the optical architecture and how the lens groups move with zoom.

    Attempted Rebuild of Nikon AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF Zoom Lens

    For lack of something better to do I purchased a partially disassembled 18-70mm lens to try to make one good lens out of the two. I was only $17.50 delivered. This one has an intact focus group but no PCB or bayonet mount and related parts. I opted to complete it using parts from the lens with the broken focus lens group since only the parts in the back were missing. The repair manual is useful for this. And aside from some partially stripped holes and melted A/M switch ;( it went together without incident, the camera recognizes the lens and even reads the zoom setting correctly (confirmed via the EXIF info). The autofocus PRM works but focus lock is only achieved if it is already very close to the optimal focus. Otherwise it womps back and forth from end-to-end of the focus range. So it could be that the focus tachometer is faulty or disconnected. It works fine with manual focus. With the mangled A/M focus switch, it cannot be set to manual focus, but autofocus can be disabled on some cameras.

    While in principle, it would probably have been better to simply swap the focus lens group into the original lens, other parts may have been damaged in the initial discombobulation.

    And that's how it will remain!

    Nikon AF-S DX Nikkor 18-200mm f/3.5-4.5G VR Zoom Lens

    There is a repair manual for this lens with detailed disassembly and reassembly procedures above the level of the VR assembly, which is common for these manuals. None have anything deeper. However, this one is quite detailed and does include the removal and installation of the VR assembly ("VR unit" as they call it).

    I purchased 4 of these to date described as "For Parts or Repair". All are in very good to excellent physical condition with little evidence of wear and no abuse. All exhibited similar problems except for ID #1:

    • ID #1 (SN: US3059848): Generally good cosmetic condition but is sometimes noisey especially when first powered up. AF is fine. The noise appears to be VR attempting to initialize but VR does not work.

    • ID #2 (SN: US3058443): Generally good cosmetic condition but focus may get stuck over part of its range if zoomed out, similar to the issue with the VR II version described later. And like that lens, zoom is sometimes hard to move in places. However, this one does seem to work most of the time, or if Zoom setting is changed a bit. The lens hood/filter ring was almost falling off originally but this turned out to simply be several loose screws. It's not clear how that could happen as these are fine thread machine screws unless it was on a vibration tester for a few weeks. ;-) VR seems dead...

    • ID #3 (SN: US3165184): Generally good cosmetic condition but focus may get stuck over part of its range though works most of the time, similar to ID #1. VR seems dead...

    • ID #4 (SN: US2576365): Generally good cosmetic condition but focus may get stuck over part of its range though it works most of the time, similar to ID #1. VR seems dead.

    VR appears to be non-functional on all of them unless I'm missing something to enable it. Yes, I've exercised both the VR ON/OFF and VR Active/Normal switches. Unfortunately, without removing the Bayonet Mount and related parts, the switches cannot be testee as they are part of the Fixed Shell. Other VR lenses work fine on the D70 including the VR II version of this lens.

    All of these had a hint of hessitent manual focus at least until exercised a bit but now work fine. This would appear to be a common problem with the 18-200 VR and VR II lenses with their physically long zoom extension. Apparently so is broken VR unless I've been extremely unlucky...... ID #1 is currently at the top of the list for dissection but it may only go deep enough to confirm there isn't a simple fix for the noisly and non-functional VR in which case the VR actuator flex cable will be unplugged to quiet it down. ;( ;-).

    There is no dissection yet, but see the Nikon AF-S DX Nikkor 18-200mm f/3.5-5.6G VR Zoom Lens Dissection Web Album. There is no dissection yet but it shows some stock photos, the dimensions, optical architecture, how the lens groups move with zoom, and a detailed drawing of the internal structure.

    These photos were taken using one of my trusty D70s with the AF-S 18-55mm ED lens that had a damaged Filter Ring. See: Repairing Broken Focus Tabs on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED Zoom Lens.

    Nikon AF-S DX Nikkor 18-200mm f/3.5-4.5G VR II Zoom Lens

    I have not found a repair manual or even an exploded diagram for this lens, though it is probably very similar to the VR (not II) version for which there is a manual. If anyone has one for this lens, please contact me via the Sci.Electronics.Repair FAQ Email Links Page.

    I do have one in mint condition and another that is cosmetically nearly as good but does not always focus reliably, even in manual mode. But there are no current plans for a detailed dissection of either, or even to investigate this lens in greater detail unless someone would like to donate a sacrificial specimen for analysis. The asking prices on eBay are way above may curiosity quotient for a lens to take apart and likely never put back together so it functions. ;-) Appropriate chants and incantations will be issued to the gods of dead camera lenses upon request but it will not likely survive the experience. :( ;-)

    • ID #1 (SN: 46156305): Near perfect cosmetic and operational condition...

    • ID #2 (SN: 46140507): Very good cosmetic condition but manual focus does not work if zoomed out beyond 100 mm or so and autofocus may be temperamental for related reasons..

    • ID #3 (SN: US46070728): Very good to excellent cosmetically. At first AF was erratic but the lens was still cold from being dropped off outside. After a warming up and a bit of exercise, it seems to focus reliably. VR seems OK but that will be confirmed once the VR Test Rig is fully operational. So this lens doesn't appear destined for dissection. Grrrr. ;-)

    • ID #4 (SN: US46026627): Very good cosmetic condition but with some of the gold paint on the lettering worn off. Excellent functional condition with smooth zoom, working AF and VR..

    However, eventually the one with the unreliable focus may end up being used for this purpose.

    But see the Nikon AF-S DX Nikkor 18-200mm f/3.5-5.6G VR II Zoom Lens Dissection Web Album. There is no dissection yet but it shows some stock photos, dimensionas, optical architecture, how the lens groups move with zoom, and the detailed internal structure of the VR version (which should be very similar). A dissection of that lens is likely to happen sooner and is expected to be virtually identical.

    These photos were taken using one of my trusty D70s with the AF-S 18-55mm ED lens that had a damaged Filter Ring. See: Repairing Broken Focus Tabs on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G ED Zoom Lens.

    Nikon AF-S DX Nikkor 18-300mm f/3.5-5.6G ED VR Zoom Lens

    This lens and its successor (below) are believed to have the highest zoom ratio - over 16:1 - of any Nikon DX lens.

    Until recently, I had not found a repair manual or even an exploded diagram for either lens, though this one appears to be very similar to the AF-S Nikkor 28-300mm f/3.5-5.6G ED VR lens for which there are repair and parts manuals from multiple Websites. However, that is FX (full frame) but even the weight is almost the same. So perhaps it really is an almost identical lens that has had its zoom range extended down to 18mm but with unacceptable distortion and/or vignetting for the FX format.

    However, as of April 2025, there is a repair manual available for the this lens at Learn Camera Repair Product 1702. There is (currently) a $3.25 charge but it well worth it. Either it appeared only recently or I missed it previously. But this manual does NOT appear to go as deeply as the one for the 28-300mm lens, specfically there is little to no information on the Aperture and VR assemblies at the heart of the lens, these being near the last parts to be removed in any disassembly. But it is better than nothing.

    Now back to the lens itself.....

    Not to put too fine a point on it, but this thing is HEAVY - 29.3 oz. (830 g), close to 2 pounds.

    Summary of the four I have so far (more below):

    • ID #1 (SN: US76000891): This lens is very worn but in good mechanical condition. Something is wrong with the alignment of one or more optical elements resulting in fuzzy photos except when stopped way down. The 1st Lens Group appears to NOT be the culprit as noted below. I'm still suspicious of something in the VR assembly coming loose even though VR works well,

    • ID #2 (SN: 72091196): Totally mint condition cosmetically and mechanically and probably optically as well, though I haven't concluded whether the minor aberrations observed under some conditions are normal for this lens design. I wanted a perfect specimen. ;-)

    • ID #3 (SN: US76003619): Excellent condition except for slightly worn "AF-S Nikkor 18-300 mm 1:33.5-5.6G ED" gold lettering. The optics are pristine, there are few if any dings or scratches on the body, and even the zoom grip is nearly new in appearance. Zoom is smooth and precise, autofocus is quick and quiet, and VR has been confirmed fully functional on my VR test stand at maximum zoom. The previous owner obviously took very good care of this lens, the wear of the gold lettering is common with all of these and I have some gold hobby paint on order to see if I can deal with that. ;-) My objective in purchasing this lens is to compare its performance to the mint one above...

    • ID #4 (SN: US76009323): Very good coondition except for slightly worn "AF-S Nikkor 18-300 mm 1:33.5-5.6G ED" gold lettering and signs of use on the zoom grip. The optics are pristine and there are few if any dings or scratches on the body. Zoom is smooth and precise, autofocus is quick and quiet, and VR has been confirmed fully functional on my VR test stand at maximum zoom. I will also attempt to touch up the gold lettering on this lens..

    The first sample of the f/3.5-5.6 version I purchased for study and possible dissection is really well used: The gold lettering is totally gone, the plastic underneath is even worn, and most of the exposed plastic surfaces have a shiny appearance. It largely works but takes truly lousy pictures. :( ;-) That's what I expected as the description stated: "the image quality is not sharp". That is totally accurate but perhaps an understatement! In fact, a pinhole camera would take better pictures. Yet there are no obvious mechanical problems - zoom and manual focus are smooth and consistent. Nothing rattles and it shows no sign of serious trauma except for some small chips on the edge of the filter ring. But the focus, zoom, and filter rings appear to be well aligned with only the typical small amount of free play that these lenses tend to have. Autofocus is fairly reliable except perhaps when zoom is near 18 mm. This may be a clue, though manual focus works over the entire range. VR works well as confirmed on my VR Test Rig. But the image quality is totally dreadful at large apertures and even when stopped down to f/32, there is serious fuzziness and color fringing over a large part of the frame especially when zoomed way in (300 mm). This suggests that a lens element or lens group may have come loose and is sitting at an angle, though the interior looks pristine with no visual evidence of misalignment or wondering elements. All the visible optical surfaces are clean without any evidence of fungus, dust, deterioration of the AR coatings, or other unsightly blemishes. The behavior can only really be attributed to misalignment of one or more elements. The label on the front is dented in one location and rotated almost 180 degrees from the normal orientation with "Nikon" at the top, so someone has probably at least removed the label and perhaps the 1st Lens Group to look inside and at the very least, they didn't pay attention to the label when it was reattached. It has no keying so that doesn't imply anything about much of anything. I can't tell if the 1st Lens Group was removed for any reason but there is a mark on it that lines up with the white dot on the Filter Ring so it's probably installed correctly. Such major abberations wouldn't even seem likely from simply being misoriented in any case. But if an asymmetric shim was out of place, that would not be obvious. I have seen at least one instance on another lens where there was only a partial shim ring. The inside looks pristine. And if any parts were left out ;) or installed incorrectly, it almost certainly would not work as well as it does, even if that isn't saying much. ;-)

    I also have a near-mint 18-300mm f/3.5-5.6 lens. But based on a quick visual inspection, it appears physically identical when viewing the inside front and back, zoomed in and out. But almost any random shot taken with it is far superior to anything the defective lens is capable of even when stopped way down.

    So I decided to see of changing the orientation of the 1st Lens Group or the location of any shims would make a significant difference.

    • Removing the 1st Lens Group is straightforward: Insert a thin blade under one edge of the label taking care not to scratch the lens glass, them lift and peel it off. It should be possible to do this with little or no damage to the label. The 1st Lens Group is held in place by 3 tabs 120 degrees apart each with 1 screw each. One of them is at the 12 O'clock position adjacent to the white dot on the outside of the Filter Ring. On this lens there is a white mark there. Assuming that is original, it can be used to orient the 1st Lens Group when it is replaced. Turn the entire lens over above a soft clean cushioned cloth and the 1st Lens Group may now fall out. If not, use the screwdriver in the mounting holes to gently assist freeing it.

      I tested the lens with all 3 possible orientations. There was no obvious consistent difference in image quality. It still consistently sucked. :( ;-)

    • Under each location where the mounting tabs go, there is a shim, each of which may have a different thickness. They may be either brass or stainless steel. I have no idea why two types of metal would be used. They extend far enough on either side to reach a pair of the 6 screws securing the Filter Ring to the body of the lens. Removing the pair of screws near each of the tab locations and gently lifting the Filter Ring enables the shim to be slid out from underneath and removed. Keep track of the thicknesses - they may all be different. DO NOT remove the entire Filter Ring for shim swapping. It is not necessary, complicates matters, and is a pain to reattach as there are several full ring shims / spacers that must be aligned with the screw holes. ;( ;-) On this lens 2 of the rings are thin brass and 1 is thicker stainless steel.

      I tested the lens in its original state, with no shims, and with only the top shim. Again, there was no consistent difference in image quality. I didn't bother with all 6 permutations, can you believe it!? And can you believe that I neglected to keep track of which side the thin and thick stainless steel shims were on, so they may be swapped. No one will know from the pictures unless the underlying problem is fixed. ;-)

    My conclusion is that the cause of the poor performance has nothing to do with fine alignment of the 1st Lens Group. It's so bad that those things are buried in the weeds. So back to square one.....

    Here is a montage of shots taken of a test chart at around 105 mm and f/5.6, 8, 16, and 32): Defective Nikon AF-S-DX-18-300mm-f3.5-5.6G-ED-VR #1: Zoom 105 mm Comparison. Zoom of 105 mm was selected simply because the chart filled the frame. (70 mm would be closer to the mean between 18 and 300 mm.) But it's no better anywhere else.

    Next, a HeNe laser beam was passed through the lens as on-axis from the input side aligned so that it passes centered through the stopped-down aperture. The beam has a near-perfect Gaussian profile with negligible scatter. The objective was to both look for the character of the reflections from the internal lens elements, and for any degradation of the quality of the Gaussian beam on a screen placed after the lens.

    On the good lens, there are a multitude of reflections but they are very weak as would be expected from high quality anti-reflection coated surfaces and can be totally superimposed in the reflection. On the bad lens, there also a multitude of reflections but 1 or 2 cannot be superimposed on the others. Exactly where they are coming from is unknown but is probably from an element before the aperture. The reflected spot is very small suggesting it is near the front of the lens but that can be confusing due to the combination of positive and negative lens elements. At first there was a bright off-axis spot which I got excited about. But that turned out to be a red herring: It was from the cheap non-AR-coated UV filter on that lens but not the other. The bad lens shows a bit of interference fringes on the transmitted beam while the good lens does not. These tests were done at a zoom setting of 18 mm. I'm not sure I'm determined enough to repeat them at 300 mm without a more stable fully adjustable test setup. ;-)

    So the 18-300 mm question is: Having eliminated 1st Lens Group alignment from consideration, what is the most likely part to fail from a minor traumatic event like whacking the filter ring or just from wear and tear? If the VR armature or its lens popped off the suspension or got stuck to one side, VR would not work at all. But VR works great. If any other lens group came off its tracks, there would be obvious problems with zoom or focus. Only if a lens element or elements) came unglued within their housing(s) could there be optical problems but no mechanical problems. If anyone actually reads this stuff ;-) and has a similar experience, knows the answer, or even has a wild guess, please contact me via the Sci.Electronics.Repair FAQ Email Links Page. For now, I'm not intending to go any further inside.

    Of note is that even perfect specimens of the 18-300mm f/3.5-5.6 lens have significant distortion and chromatic aberration of varying degrees over various portions of the zoom and focus range. Achieving decent performance over a greater than 16:1 zoom range is challening. But modern DSLRs digitally process the images to largely correct both geometric distortion and color fringing using lens-specific data stored in memory (part of the camera firmeware). So the end-user may never see most of these. unless they are obsessive-compulsive and search for defects like that. It may be surprising how mediocre its performance really is when viewing the raw image data. And this lens has 19 lens elements. That's 38 anti-reflection-coated surfaces the light must traverse, which will have some effect on general sharpness, flare, etc. (But none of that can be corrected in-camera.)

    Being slightly disappointed with the performance, I even contacted Nikon via their Website with the serial number to see if they would tell me anything about that specific lens but of course that was hopeless. Their reply was that they don't have any information and suggested that I send it in for service. ;( ;-)

    And a trivial triviality common to both (and I assume to all of these): The zoom marking for 200 mm seems to correspond more to somewhere between 225 and 250 mm, NOT 200 mm based on the image size compared to the 300 mm position. I've not seen any mention of that in the reviews of this lens or on Nikon lens forums.

    How far it goes will depend on when - if ever - the cause of the lousy pictures can be found. My guess is a lens group that has been knocked out of position, or perhaps the VR Lens Group even though VR appears to work well. If one of the springs in the VR assembly popped off, VR might still appear to work.

    For the start of a dissection, see Nikon AF-S DX Nikkor 18-300mm f 3.5-5.6G VR Zoom Lens Dissection Web Album. This will be guided by the repair manual but there will be significant deviations. ;-)

    And yes, you aren't hallucinating. There are closeups of a piece of cloth and shots of an ancient digital computer light and switch panel amongst the dissection photos. The reason for these is explained later below. ;-)

    Here are some more comments on the dissection photos:

    • The first four are stock photos showing this lens by itself and in comparison with the other large-zoom range lens and the AF-S DX 18-55mm f/1:3.5G VR II kit lens.

    • The next two show the optical design of the lens and the approximate position of the lens groups at various zoom settings. These were measured so they should be fairly accurate. (If interested, load the image at full resolution by using this filename: AF-S-DX-18-300mm-f3.5-5.6G-VR-Lens_Group_Positions.jpg in the same folder. Then the scale is 100 pixels/inch.)

    • The photos bookended by the Nikon boxes are of a pristine sample of this lens.

    • After that are photos of a test chart showing how dreadful the defective lens really is.

    • Next are photos of that lens as the front is discombobulated for the dissection. Every attempt has been made to do this in a reversible manner. That may be asking a lot but so far the only casualties are the Large Light Shield, which tore upon removal, and the locations of the 3 partial shims under the 1st Lens Cluster. But it was never certain that they were in the correct positions at all when I acquired the lens, and then after I did some initial exploration.

    • The next set of photos show images taken with this lens of a piece of cloth and 35 mm Kodachrome slide positioned at the magic "sweet" spot described below at various apertures, and then a comparison of a shot of the same slide taken using a AF-S DX Micro Nikkor 40mm f/1:2.8 Macro lens with home-built slide copying adapter. More on these below.

    • The next set of photos of the computer console were made with the same slide adapter as for the full frame shot using the Macro lens, but used with this lens instead. In another coincidence, the coverage was nearly the same. Focus was carefully adjusted at the center. As can be seen, the quality is totally dreadful - much more so than the previous shots - and a bit inconslusive. However, perhaps of note is that the fuse holders in the lower part of the console remain is focus relative to the upper left even at f/1:5.6. In fact, focus at the center appears worse, which is strange. But, the sharpness is actually better at f/16 than f/25. There is little or no pincusion distortion. ;-) A better test slide is needed.

      For the record, in the "well that's interesting but probably of little value for anything department", some typical Field of Views (FoVs) are very approximately:

         Zoom    Location      FoV       Notes
       -----------------------------------------
         18 mm     7.0"    2.0" x 1.33"
         20 mm     6.0"    1.5" x 1.00"   FX 
         30 mm     2.5"    1.0" x 0.67"   DX
         70 mm     0.0"    0.5" x 0.33"
         90 mm    -0.4"    0.4" x 0.27"
      

      where "Location" is the distance from the edge of the Filter Ring. Since the optical elements comprising the AP/VR assembly can be modeled as a single convex lens, this is just basic ray optics, more-or-less, with worse performance than a bog standard pin-hole. ;-)

    • The photo of the red blob was made by passing the beam of a HeNe laser expanded to approximately 12 mm through the lens to a screen at a distance of around a meter. The rings are in the original beam from an HP 5517 laser tube assembly. The ripples are from dust somewhere in the optical path. And the ding on the right it a defect in the beam expander output aperture.

      The key takeaway from the shot is that the ring pattern is fairly symmetric. And it doesn't change much shifting the lens angle, moving it from side-to-side, or flipping it end-for-end. In addition, the beam focuses to a tiny dot just after the lens, which is also symmetric in front and behind that point. Taken together, the results are really strange and pretty much eliminate this last remaining lens cluster as the cause of the lousy lens performance. But given everything else, there is no other possibility!

    • The last 11 shots show the reassembled lens and sets of closeup photos at a Zoom of 300mm and apertures of f/5.6, f/8, f/16, and f/32 of a cheap compass and antique pocket watch movement.

    Now for more details.

    The first part of the dissection dealt with removing the Front (1st) and Middle 1 (2nd) lens clusters. They appear pristine and there is nothing obivous inspecting beyond those from the front. There is evidence that 2nd Lens Cluster had been removed previously but I can't rule out that being my doing.

    ThAt state of disassembly offered a possible way to confirm that the problem was still present and associated with the back of the lens. It turns out that with the 1st and 2nd Lens Clusters removed and Zoom set at 18 mm, an "object" against the front of the Zoom Barrel (just behind the edge of the Filter Ring) will be in sharp focus in the camera. Whether there is some cosmic significance to this with respect to the lens design is not known but it is a remarkable coincidence. ;-) The area covered is around 1.0 x 0.6 inches, close to the APS-C DX format. So a 35 mm slide (remember those?) or 35 mm negative, a textured surface, or something similar can be secured there with masking tape. If it is too close, Zoom can be used for manual focus since it moves that surface without affecting anything else significantly over the small range required. (Focus would not do anything without the 2nd Lens Cluster installed.) There is a small amount of pincushion distortion but one can't have everything. ;-) And a photo editor like Evoto will easily correct that. Preliminary results are encouraging in confirming the problem is with the back section of the lens:

    The photos titled: AF-S-DX-18-300mm-f3.5-5.6G-ED-VR_No_1st_2nd_Lens_Clusters_Cloth1_f5.6, f8, f16, and f29 were taken using a D5600 of a piece of fine thread cloth positioned at the lens's sweet spot using similar aperture settings to the test chart photos. The same asymmetric fuzziness appears to be present.

    The photos titled: AF-S-DX-18-300mm-f3.5-5.6G-ED-VR_No_1st_2nd_Lens_Clusters_Univac_1830_Console_Slide1_f5.6, f8, f16, and f22 are of a 35 mm Kodachrome slide originally taken in the year 1978 using a Nikon Photomic FTN body with f/1:1.4 50 mm lens of the operator's console of a Univac 1830 (CP-823/U) avionics computer prototype from the early 1960s. (For some obscure reason the D5600 refused to stop down beyond f22 for these shots even though it was set to Manual exposure.)

    (For the techno-dweeb types and having nothing to do with this lens, the Univac 1830 was a 30 bit computer that had a whopping 32,768 words of core memory and utilized flat-pack SSI integrated circuits for most of its logic. Wikipedia CP-823/U has more including a photo of the nine massive electronics boxes that comprised the actual computer, all of which I had at one point along with two or three cartons of garden-hose diameter cables. The photos of the console there are ones I contributed. The first one is derived from a scan of the exact same slide used for this dissection. These may be the only color photographs of the 1830 in existence today.)

    For comparison, the photo titled: AF-S-DX-18-300mm-f3.5-5.6G-ED-VR_Univac_1830_Slide_with_Macro_Lens1 was taken of the same slide using an AF-S DX Micro Nikkor 40mm f/1:2.8 Macro lens with the slide mounted approximately 2.5 inches in front of the lens with a light diffuser and cropped to show the entire 35 mm frame. This is a fairly accurate comparison of the area of the original slide and the smaller coverage of the hacked 18-300mm lens along with its pincushion distortion.

    Next was the dissection of the back of the lens. The Back Lens Cluster also appears to be in perfect condition - at least until I disassembled the two sections with the 12th and 13th Lens Clusters and 14th Lens Cluster, which is something that should not be done without the proper tools and test procedures to realign them!)

    But here again, the lens cooperated in that with *only* the Aperture/VR assembly still present, the lens would focus as a macro lens over a range of a few inches.

    And the shot of the laser spot seems to rule out the AP/VR Lens Cluster as the cause of the problem. Which means the lens should have performed flawlessly. Too bad that it didn't understand that. ;-)

    I decided to put it back together. It was straightforward since nothing except the one Light Shield was damaged Using the same laser, it should be possible to align and reassemble the Back Lens Cluster. It's just a matter of screwing the 2nd Lens Cluster (Focus) back in. And while the location of the shims for the 1st Lens Cluster are suspect, any effects from them being arrange incorrectly should be small.

    Everything has been reinstalled except for the label, light shields, front lens cluster shims, and rubber boot. The back lens cluster lens groups were centered as best as possible without going to the extreme a laser. ;-) The last photo in the Web Album shows the reassembled lens. The lens still takes truly lousy pictures. It's hard to tell if they are worse than before since they were already terrible. And it's also hard to tell if the character of the faults has changed as a result of alignment or anything else, but it's not dramatically worse. Probably no more than additional flare resulting from the lack of the light shields.

    And that, as they say, is that. ;-) Deeper dissection of this specific lens is probably not going to happen. However, if someone has a certifiably dead sample of the AF-S DX 18-300mm f/1:3.5-5.6G ED VR lens they would be willing to donate to the cause, please contact me via the Sci.Electronics.Repair FAQ Email Links Page.

    Nikon AF-S DX Nikkor 18-300mm f/3.5-6.3G ED VR Zoom Lens

    This is the newer and lighter version of 1the 18-300 mm lens but it has lost a fraction of a stop at the high end - 6.3 versus 5.6 which is considered mostly irrelevant with modern DSLRs. Its weight is 19.4 oz. (550 g), about 2/3rds that of the 18-300 mm f/3.5-5.6, which is actually slightly less than that of the 18-200 mm VR II lens - 19.8 oz. (560 g). It must use a lot more plastic! :( ;-)

    I am not aware of any on-line service manual for this lens, which appears to differ significantly compared to the previous 3.5-5.6 version (above, for which there is a service manual).

    • ID #1 (SN: US6001635) This is a certifiably broken sample and it was used for the first block of dissection photos, below. But not inside. The main issue is that VR does not do anything useful. That could be as simple as a bad switch or wire that came off. This is a well used lens but focus (A and M) are both functional. And though zoom is a bit hard to move at times, nothing appears really damaged. But there is a serious nick in the lens hood mount ring (visible in a few of the photos) so it has experienced some trauma.

      See the Nikon AF-S DX Nikkor 18-300mm f/3.5-6.3G VR Zoom Lens Dissection Web Album.

      This lens does take photos as long as one is careful to avoid camera shake, so reducing it to parts may not happen for a while. But the back was opened to check for obvious problems. The flex cables were all secure and the VR switch was tested so an easy fix is unlikely. However, if removing the bayonet and related parts, make sure to record the precise location of the brass shims - which I of course neglected to do initially. This specific sample has 2 and they are not identical so the orientation and also which one is on top may matter, though it's not clear why. And when reinstalling the aperture tang, take care that it goes into the correct location in the aperture actuator. Unlike many other lenses, it's a rectangular hole on this one, not just cup or U-shaped lever. It can slip in outside the hole and while it may appear to work when first installed, when the Inner Ring is put in place, it will jam. Other than that, reassembly is quite straightforward. There are only 4 types of screws and where they go should be intuitively obvious. ;-) But some are quite small so losing them is too easy and would be bad. ;-( And don't overtighten them!

      As they say: "If it ain't broke, don't fix it.". After going inside, two things changed: First, the image through the viewfinder "jerks" initially when the camera is turned on and the shutter is pressed, but only when VR is on. However, VR still doesn't do anything else. This indicates that VR is being powered but is jamming to one side unable to initialize. I don't think VR did anything when first testing the lens. So perhaps that's an improvement. ;-) Second, autofocus stopped working reliably. I could have sworn it wasn't like that initially. Sometimes it would lock but usually it would either get stuck at one end of its range, or continue hunting back and forth around the optimal focus unless very close, in which case it might lock. So the back parts were removed again and it was discovered that one of the brushes in the Focus Encoder wasn't contacting the encoder strip. I have no idea how that could have occurred during the excursion inside as it's safely recessed. But once the brush was "adjusted", autofocus is back in shape. The microbrain had no idea where focus was at any give time so it didn't know what to do. Poor thing. ;-)

      I also reseated all the internal flex cables at the same time as dealing with the focus issue but that didn't make any positive difference to VR.

      However, now the lens produces 4-1/2 "clunks" about 1/2 second apart when the camera is powered up and sometimes when it's powered down regardless of whether VR is on, independent of zoom and focus settings, but only with autofocus enabled. They sound like they are coming from the vicinity of the VR assembly but don't appear to do anything to the image in the viewfinder. The count of 4 is digitally precise and the behavior is totally repeatable. Go figure.

      Having said all that, the lens takes great photos and therefore I have no plans to go inside again. If only it could be filled with helium so it would weigh less (though it is actually a tad lighter than the 18-200 mm VR lens). And the older version was even heavier so see the info on it in the previous section, above. ;-)

      Of course all great plans need modification at some point. With the acquisition of ID #2, the 1st Lens Cluster was used for a transplant.

    • ID #2 (SN: US6063861) Unfortunately, in principle this could be more involved than just swapping the optic though how true that may be in practice is still not known. For the 18-55mm f/1:3.5-6.5 lens, there may be one or more full spacer rings and many small shims at 120 degree locations. It is believed that these are associated primarily with the 1st Lens Cluster, and not the overall lens since the molds and machining should be very precise. In that case, the orientation of the 1st Lens Cluster is also critical and must be retained, so label it relaive to the main index mark! But it is also possible that they compensate for variations elsewhere. (I should have first simply swapped the 1st Lens Cluster without messing with the spacers and shims at all to see how well that worked. It might have been fine. Oh well.) Loosing track of where they came from or loosing them entirely is all too easy. Thicknesses were measured to be approximately 0.001" for the stainless steel shims, 0.002" for the copper shims, and 0.004" for the brass shims. (That may also be true of the spacers but I didn't check their thicknesses.) So it is a binary 1,2,4 relationship to simplify selecting a specific thickness. The first rule is to keep track of exactly where they were originally located. That is particularly challenging given that the shims for this lens are very small and tend to jump out of position and fly away. The spacer rings which tend to be thicker (but not always) and thicker shims would be most critical but the thinner shims could possibly impact edge sharpness for low f-number shots. I think the shims were restored in the correct locations but it's hard to tell. Even picking them up and positioning them is virtually impossible. In the end, a piece of double-sticky tape wrapped around a small screwdriver was used to pick them up and place them on the locating pegs while then holding them in place with a toothpick. Fingers and tweezers were useless.

      If just swapping the 1st Lens Cluster would have been sufficient, that is possible without disturbing the spacers or shims: Remove ONLY the three 1st Lens Cluster mounting screws and lift it off taking care that if any shims come away with it, they are replaced in the same location. DO NOT remove the the Filter Ring since it holds the spacers in place.

      The spacer ring(s) and the thickness common to all the shims will slightly affect the closest focus distance and possibly being even able to focus at infinity if too much thickness is present. So, in conjunction with the spacer ring(s) at the back of the lens, they may be used to tune close focus distance. But exactly how much the slight tilt imparted by the unequal shims really matters is questionable give the HUGE free play present in most of these lenses - which easily exceeds any shim thickness differences.

      Regardless, after reassembly the lens appears to work perfectly and the photos it takes are excellent. The focus range and autofocus go a bit closer than the spec value by a couple inches but includes infinity at all zoom settings so that may be within acceptable limits. I have not checked the EXIF metadata. There are no obvious sharpness issues, asymmetric or otherwise.

      In the future, I would suggest measuring the close focus distance at maximum zoom before changing anything and then swap only the 1st Lens Cluster. Re-check performance, particularly the close focus distance. If that hasn't changed significantly (say less than 1 inch for this model lens) and the lens otherwise seems acceptable, don't worry, be happy. ;-) The EXIF metadata values may be not be precise, but they are not precise to begin with, depending on the focus encoder values. I kind of doubt that the focus servo tuning will be affected enough to matter, if at all. Any edge sharpness issues may only be detectable by taking high resolution photos of a resolution chart on a test stand and not in real life. And maybe not even then.

    Nikon AF-P DX Nikkor 70-300mm f/4.5-6.3G ED Zoom Lens

    There appear to be no on-line repair manuals for this or any of the other AF-P lenses.

    The AF-P DX Nikkor 70-300mm f/4.5-6.3G ED is relatively lightweight with a greater than 4:1 zoom range. But it's too bad that the lower end of the zoom range doesn't extend to the 55 mm of the AF-P 18-55mm lens. It's all plastic construction is fine except that for a long lens like this, the bayonet mount should probably have been made of metal for robustness. Even the bayonet mount on the much shorter 18-55mm lenses gets destroyed quite frequently. This one is more prone to such failures. Replacements are available.

    This is 1 of only 3 types of AF-P DX lenses using the so-called "pulse" stepper motor focusing system. The most common is the AF-P DX 18-55mm f/1:3.5-5.6G VR "kit" lens. The third is the AF-P DX 10-20mm f/1:4.5-5.6G VR wide angle lens. There would probably have been more but Nikon was transitioning over to the mirrorless "Z" cameras at around the same time the AF-Ps came out. Z lenses use similar stepper motor technology for focusing.

    Both VR and non-VR versions of the AF-P DX Nikkor 70-300mm f/4.5-6.3G Zoom Lens are available, which are believed to have virtually identical construction, so most of what follows should apply to both. (The AF-P FX Nikkor 70-300mm f/4.5-6.3E ED VR lens may be significantly different with among other things metal Bayonet Mount and electronic aperture control with no aperture lever - thus the "E" after the f numbers. (Ask Google what the "G" in the other lenses stands for. It's... amusing.) The latter is also consistent with the transition to Z gear being what that uses but it is supposed to be compatible with late model DSLRs.)

    A partial dissection of the non-VR version may be found at: Nikon AF-P DX Nikkor 70-300mm f/4.5-6.3G ED Zoom Lens Dissection Web Album.

    Nikon AF-P DX Nikkor 70-300mm f/4.5-6.3G VR lenses:

    • ID #1 (SN: 21019592): Very good to excellent cosmetic condition and appears to be fully functional, AF and VR tested...

    • ID #2 (SN: 20076766): Very good to excellent cosmetic condition except for "click" when adjusting Zoom in the vicinity of 210 mm. But appears to be fully functional, AF and VR tested...

    • ID #3 (SN: 20966522): Very good to excellent cosmetic condition except for busted Bayonet Mount. The Bayonet Mount / Back Shell from Non-VR ID #1 was swapped. The annoyance is that it will not have "VR" displayed on the label. Well, one can't have everything. Swapping the labels might be possible but the results cosmetically could be a disaster. This also means it has the SN from non-VR #1...

    • ID #4 (SN: 20552214): Very good to excellent cosmetic condition, perfect functional condition, VR tested...

    • ID #5 (SN: 20390659): Very good to excellent cosmetic condition, perfect functional condition, VR tested...

    • ID #6 (SN: 21019633): Near perfect cosmetic condition, perfect functional condition. AF tested, VR pending but makes the correct noise. ;-)

    Non-VR Nikon AF-P DX Nikkor 70-300mm f/4.5-6.3G ED lenses:

    • ID #1 (SN: 20914467): Very good to excellent cosmetic condition. But the focus assembly has been displaced or is broken. This lens is used for the photos in the dissection, above. Damaged Back Shell / Bayonet Mount from VR #3 swapped, still reasonably secure.

    General comments:

    • The Bayonet Mount and Rear Shell are a single molded plastic piece just like the AF-P DX 18-55mm lens. It may be replaced without detaching any cables. This is not true of most AF-S lenses.

    • The Camera Contacts are held in place by the Rear Cover Ring without their own assembly. So they all fall out when disassembling the back of the lens. This is true of all the AF-P lenses. As long as that is expected, it isn't really a problem.

    • Replacing the Front (1st) Lens Cluster or Rear Lens Cluster is straightforward without extensive disassembly. However, whether each is truly interchangeable between samples of the lens is not known. But there were no shims or spacers on the sample lens. Going deeper is more involved and appears to be a major undertaking. That would be required to repair the focus mechanism. Stay tuned.

    The specific lens in the dissection, above, shows no signs of trauma. However, the focus optics are way off-center. Focus only works even remotely correctly over a narrow range of Zoom, and only clicks otherwise. The resulting photos even if the camera thinks it has focus lock are dreadful, Something in the focus mechanism has broken and/or popped out of place resulting in one or more lens elements being shifted and/or tilted. If this were a VR lens, I would blame that, it isn't. This could conceivably be a simple repair, but so far, even after taking the lens largely to bits, the focus assembly is still not accessible. Stay tuned.

    The conclusion so far though is that if there is any problem with the focus mechanism, get a replacement lens. :-( It is buried so deeply inside that the entire thing needs to be disassembled to get to it, let alone to fix the problem. Focus issues in the equivalent AF-S DX lens are trivial in comparison. And NO detailed information could be found on-line with or without the assistance of AI. This assessment may change if I find a totally smashed sample to disassemble. It may turn out that there is a shortcut to getting to the focus assembly. There are a pair of small screws and pegs which I orginally thought had to be removed to remove the Zoom Barrel and related parts. But they may be securing the focus assembly. ;-) Interestingly, after partially disassembling the lens and then putting back together, the focus assembly offset seems to be smaller. Go figure.

    For many other problems, access is straightforward. The simplest repair (which is very common) is to install a replacement Bayonet Mount / Rear Shell. They are available for around $25 but the replacement will not have the Aperture lever assembly, so that would need to be transferred. If swapped from a similar lens, then it's even simpler. It's the same procedure as repairing the AF-P DX 18-55mm lenses - a bit fiddly but all screwdriver work and can be done without even unplugging any ribbon cables. See the section: Nikon AF-P DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Bayonet Mount Transplant.

    Nikon AF-P FX Nikkor 70-300mm f/4.5-5.6E ED VR Zoom Lens

    There appear to be no on-line repair manuals for this or any of the other AF-P lenses.

    The AF-P FX 70-300mm lens is the only full frame AF-P lens. There isn't even a "standard" or "Kit" AF-P FX lens. The assumption is that Nikon terminated designs for new AF-P lenses to concentrate on Z lenses, which share some of the same DNA. But interestingly, there is no 70-300mm Z lens either. This lens may also be the first one to have an electronically-controlled aperture (thus the "E" after the f/ numbers). With the aperture lever gone, there is no longer any real way to manually open the aperture to inspect inside the lens. This is also the only AF-P lens to have physical switches for focus (A/, M/A, M) and VR (Off, Normal, Sport). There is an AF-S FX 70-300mm f/1:3.5-5.6G VR lens but its construction is quite different.

    While largely of plastic construction, this lens is HEAVY - 24 ounces or 1.5 pounds (680 g). Most of that weight is probably the glass optics. Although slightly larger than the DX version, they look generally similar except for the location of the Focus Ring and the metal Bayonet Mount for the FX version. And sellers on eBay sometimes confuse them. Note that there is little point in acquiring this FX lens if you don't have a full-frame camera or expect to upgrade to one. The DX version is just as good and typically less than half the price.

    Nikkor 70-300mm AF-P FX f/3.5-5.6E ED VR Lenses:

    Probably only these samples as I do not have and do not expect to acquire any full-frame F-mount cameras! Unless really good deals present themselves. ;-)

    • ID #1 (SN: 2011405): Excellent to perfect cosmetic condition as though it has never been used, but focus only works over part of the Zoom and/or Focus range and it is not totally consistent. This was initially thought to be a mechanical problem, which is common with lenses like the AF-S DX 18-200mm. But a Web search seems to point to either a bad ribbon cable (makes sense) or focus motor (not so much). Unfortunately, the optimal focus position varies by both the Zoom setting and subject distance, so it's a crap shoot as to whether there will be focus lock for any given shooting situation. When it works, it works well, for what that's worth. The only Zoom setting where it seems to be fairly consistent is near 300mm, where it will usually focus from 1.2m (spec'd minimum) to ∞. Focus issues appear to be relatively common with this model lens and may be more than it's worth in either labor or cost to remedy since like all the AF-P lenses, the focus mechanism is buried rather deep inside. There may also be aperture issues over some or all of the Zoom range where it works at all. A cracked ribbon cable would be consistent with both.

      Monitoring for electromagnetic emissions from the lens with a dozen turn coil underneath seems to indicate that there are no pulses being generated when Focus does not change, not that it is mechanically binding. But this is far from conclusive as it's conceivable that movement is needed to generates detectable EM pulses.

    • ID #2 (SN: 2010336): Near mint cosmetic condition and appears to be in perfect functional condition. Test of VR on the shaker stand still needs to be performed, but it makes the correct noise when VR is active.

    • ID #3 (SN:): Appears to be in mint cosmetic condition, focus described as bad. That could be either simiilar to #2 or testing on an incompatible camera. TBD.

    Nikon AF-P DX Nikkor 10-20mm f/4.5-5.6G VR Zoom Lens

    There appear to be no on-line repair manuals for this or any of the other AF-P lenses.

    This is a nice light-weight wide angle lens. 10-20 mm is equivalent to 15-30 mm for the FX and old 35 mm film format. It slightly overlaps the range of the 18-55mm "kit" lens at the high end. As noted in the previous section, this is 1 of only 3 AF-P DX lenses with different focal length ranges currently and probably forever.

    Nikon AF-P DX Nikkor 10-20mm f/4.5-5.6G VR lenses:

    • ID #1 (SN: 261895): Very good to excellent cosmetic condition and fully functional, AF and VR tested.

    • ID #2 (SN: 223836): Very good to excellent cosmetic condition and fully functional, AF and VR tested...

    • ID #3 (SN: 296490): Well worn (shiny plastic) but still in decent cosmetic condition with no significant scratches or dings though there is peeling ink on the label. However, the rubber zoom grip doesn't seem at home on this lens as it is very slightly too large length-wise. Perhaps it is a mis-matched transplant (though I cannot determine from what lens) or one from the Far East that doesn't quite fit. There are no real signs of deterioration as it is still supple and resilient, not flabby or stretchy indicating rubber decay. Soaking the rubber grip in boiling water for a half an hour made no difference. ;-)

      But functionally, the lens is a disaster. While it is recognized by the camera, focus does nothing (both AF and M) and there is a grinding noise when the camera is powered on attributed to failed VR initialization, and delays Live View or shutter response until it settles down. There is also a very slight roughness of the Zoom Ring near the 20mm position. The EXIF data does appear to show that the approximate Zoom setting (based on the encoder in the lens) is being sent to the camera. My guess before going inside was that there is a damaged or loose cable. However, after removing the parts from the back of the lens (Cover Ring, Bayonet Mount, and Back Shell), there is no obvious evidence of trauma to any cables, connectors, or the PCB. And after reseating cables and expanding the 8 Camera Contacts so they make, uh, better contact, there was no change in behavior upon reassembly.

      A couple days later on a whim - having not done anything with the lens other than to fondle it a bit ;-) - I stuck the lens back on a D5600. And focus worked perfectly (both AF and M) and even VR appeared to be functional on my test stand. (The stuttering at power-on from VR is sometimes present but that is infrequent and didn't take place on the test stand.)

      Then it stopped working - and started working again - and stopped - and started. ;-) A classic intermittent, though it doesn't seem to correlate with anything; Focus is either fully functional or totally dead after the camera is turned on. If it works, it appears to be reliable. So perhaps it's an initialization issue. The obvious solution then is to never turn the camera off! ;-) But it seems to be becoming more reliable as time goes on. It just sometimes needs a few power cycles to cooperate.

    • ID #4 (SN: 352789): Very good to excellent cosmetic condition and fully functional except VR needs to be tested.

    A Web Album with some views of ID #2 may be found at Nikon AF-P DX Nikkor 10-20mm f/4.5-5.6G VR Zoom Lens Web Album.

    And a Web Album with the early stages of the dissection of ID #3 may be found at Nikon AF-P DX Nikkor 10-20mm f/4.5-5.6G VR Zoom Lens Dissection Web Album.

    More to come, perhaps.

    Nikon AF-S FX Nikkor 28-300mm f/3.5-5.6G ED VR Zoom Lens

    There is a repair manual on-line for this lens. Search for "Nikon AF-S Nikkor 28-300mm f3.5-5.6G ED Lens Factory Service Manual" (without the quotes). It's the first hit using Google. Though now it seams that the Learn Camera Repair Website is charging a small amount for these manuals. It is worth the cost just for the information value even if you have no intention of disassembling the lens. But if you're a cheapskate, it's still free at ManualsLIB.com (as of April 2025).

    This a full frame (FX, 35 mm) lens so it really has no business being here. ;-) Actually, it does. An FX lens will work fine with a DX camera. It's just a bit of a waste since ~half the picture area is outside the DX frame. The main reason it IS here is that its construction is believed to be very similar to that of the DX 18-200mm and 18-300mm lenses AND one was found on eBay just over $125 that is optically in very good condition but certifiably very broken mechanically - something is loose/rattling around inside including aperture parts which hvae been mangled, and the aperture is always wide open (but partially blocked by the parts floating around inside the lens!), Zoom gets stuck with serious dragging and grinding and doesn't go out beyond ~32 mm (never to 28 mm), focus is temperamental, VR seems dead, and there may be a motorized ratcheting noise when first powered. Aside from those minor issues, the lens is in perfect operating condition. ;-) And it does take decent photos when it feels like it (if you don't mind the aperture being more or less wide open). ;-) In any case, mostly complete dissection has been performed - as far as necessary until the sources of the problems are located - which is down to the level of removing the Aperture and VR assemblies. Which is to say, a nearly a total disassembly.

    See the Nikon AF-S FX Nikkor 28-300mm f/3.5-5.6G VR Zoom Lens Dissection Web Album. (The first few are all either Nikon stock photos or those from the KenRockWell.com Website (which appear to include some Nikon stock photos!), then the lens architecture diagram, after that are all of the distressed lens itself. Those photos were taken with a Nikon D90 using a Nikkor AF-S DX 18-55G VR II lens on a tripod without VR (it's dead on that lens anyhow) and remote shutter release. Most are illuminated by a ~16x16 inch LED fixture with a uniform diffuser ~16 inches above the shooting area. The camera's White Balance is set to Fluorescent Cool White and minor picture adjustments are done in post processing. The background is a single sheet of glossy white paper. There has been no background removal partially because those programs that generate images with decent resolution are no longer free as they were for the earlier dissections, or are now too cumbersome to use with multiple photos. But with the white background for most, there is little need for it. Those without a white background were done that way to enhance the appearance as needed.

    The first block of photos after the lens architecture diagram show the intact lens. The shiny complexion is not an artifact of lighting, it definitely appears that way having seen lots of use, but no actual physical trauma is evident. The broken aperture actuator plate or a piece of it is visible in the view through the front of the lens. ;-)

    The dissection will be guided by the disassembly procedure in the repair manual, skipping those steps that are irrelevant. A substitute for at least one special tool may need to be improvised. While a reasonable effort will be made to avoid unnecessary destruction, some damage will almost certainly occur. But the aperture mechanism is already history and there has likely been irreversible havoc caused by the crunching and grinding during Zoom and other scary sounds from Autofocus. Live with it. ;-)

    The next 15 or so photos after the lens architecture diagram are of the intact lens. Then the fun begins. The next block of photos are based on the disassembly procedure in the repair manual starting at the front of the lens. So, removal of the Filter Ring, 1st Lens Group, and 2nd Lens Group. The checkered yellow and white background is used for some photos of the lens group parts to give more depth to them. There is also a photo of the two pieces of the aperture mechanism that were floating around inside. The one on the left - the Aperture Actuator Plate - is missing the actuating tang and was originally totally folded in half! And the one on the right had to be partially folded to extract it through the hole left by the 2nd Lens Group. With those removed, Zoom is reasonably smooth and the crunching noises are gone. However, the aperture return spring is missing and Zoom still does not go below around 32 mm, possibly due the missing spring and/or tang being jammed in there somewhere. The missing aperture leaves probably wouldn't account for it.

    As the dissection has progressed further at the back of the lens, several mangled remains of the aperture leaves have fallen out. Three at first, then after removing the Main and SWM PCBs, three more along with a metal tang broken off the Shutter Actuating Plate, and the final three after the lens was disassembled down the Zoom Telescope Mechanism (my terminology). ;-) And the aperture return spring was found in-place with one end still attached by a dab of adhesive. That metal piece may have been what was interfering with Zoom because now the full range has been restored. If the lens was only used for shooting at the wide open 1:3.5-5.6 aperture (using aperture priority or manual control), it could now be reassembled in perfect condition. ;-) That's tempting but there is probably little demand for a lens that only works at maximum aperture. The aperture assembly for this lens doesn't appear to be something that appears on eBay! ;-( ;-)

    The dissection is now complete. The assembly that wasn't totally taken to bits is what the Repair Manual calls the "2nd lens-G straight ring unit". It's a pair of concentric cylinders with screws, guides, bearings, and springs which would like nothing else than popping off and getting lost. Otherwise, it's pretty much as described in the Repair Manual, though some steps were done out of order by accident or by design. As best as I can determine, nothing has been damaged so were an aperture assembly for this lens to appear on eBay at an affordable price I might consider attempt a restoration.

    One interesting observation is that the VR Gyro ICs (PN: XV-3500CB) are on the Main PCB and SWM PCB, rather than having a separate assembly of their own. The PCBs are mounted at right angles to each-other.

    Stay tuned.

    Nikon Z Lenses

    The Nikon Z cameras use a new series of lenses with a totally different mount. This was done in part because the lens-to-focal plane spacing of the Z cameras is much smaller, as well as due to electronics changes in the control of aperture, focus, VR, etc.

    The general scheme is the same for mounting and unmounting, but the Z mount is much larger in diameter, the ball contacts face forward in the camera instead of being in the lens facing inward, and there may be many more of them. Both FX and DX format lenses are automagically accomodated. Since Z lenses all use a pulse-type focus scheme similar to that of AF-P lenses, there is no direct support for the AF-S "Silent Wave Motor" (SWM) focusing.

    FTZ and FTZ-II F-to-Z adapters enable F-mount lenses to be used on Nikon Z cameras. They trick the Z camera microbrain into thinking there is a Z-mount lens attached to the adapter when it is actually an F-mount lens. This includes full electronic control of aperture and focus. But there are no optics inside, just the correct physical spacing to account for where the mirror mechanism would be in a DSLR. And motors and electronics to operate the aperture lever and focus mechanism. I am not aware of any adapter in the reverse direction. ;-)

    Nikon Z DX Nikkor 16-50mm f/4-5.6 VR Zoom Lens

    There is a repair manual for this lens available directly from the Nikon | Self Service Repair Website. Yes, there is now such a thing direct from Nikon no less which apparently is quite recent and only deals with Nikon Z gear. That is the good news. The bad news is that for this specific lens, it has virtually no useful information. In fact the number of pages devoted to notices, cautions, and warnings - most of which are totally irrelevant for a lens - outnumber those with repair information. However, some other repair manuals are much more comprehensive. So worth checking out in any case.

    The Nikkor Z DX 16-50mm f/3.5-5.6 VR lens is the most compact zoom lens for Nikon Z cameras. Its reviews are actually pretty good for a mostly plastic (except for the optics) lens. The optical architecture is simpler than other lenses with a similar zoom range, specifically the AF-P and AF-S DX 18-55mm "kit" lenses - only 7 optical elements versus 12 for the AF-P 18-55mm. Of course their minimum aperture is larger by an extra fraction of a stop. ;-) A comparison of these two lenses is shown in Nikkor Z DX 16-50mm f/1:4.5-6.3 VR Z vs AF-P Comparison1. While the zoom range for the AF-P is also wider by around 10 percent, these don't account for its dramatically larger size. But this diminutive lens does look a bit silly on a massive Z SLR, sort of like an ancient Kodak. ;-)

    The Z 16-50mm is also the least expensive Nikon Z zoom lens and broken samples are available at relatively decent prices - which is perfect for evaluation and dissection. ;-) In fact, it may be the ONLY affordable sacrificial Nikkor Z lens likely to show up on eBay more frequently than total solar eclipses. Anything Nikon Z-related seems to be at least 4 times the cost of Nikon F gear. And many other Nikkor Z lenses approach $1,000 and beyond, even used.

    Note that when mated to a full-frame (FX) camera, the coverage for this lens is DX: AFS-C or around 1x0.6 inches. The Z full frame cameras know that and will crop the photos auto-magically. So except for giant blowups, that may not even be noticed.

    I have two samples of this lens:

    • ID #1 (SN: 20141340): This was described as having "front end damage". I wonder if their collision insurance covered it. ;-) And indeed, the Zoom Barrel was jammed at an angle and split along its entire length with the sections shifted with respect to each-other by a several mm. In fact, the entire front section of the lens was so cockeyed that zoom would not move at all. However, some gentle persuasion remedied that so the lens works mechanically even with the split Zoom Barrel. But the front Lens Cluster was also pushed in on one side by a couple of mm with trauma to the label evident. This results in it taking truly lousy picture with focus varying from side-to-side across the field of view.

      After removing the label, the problem could be easily seen: Two of the three plastic supports for the 1st Lens Cluster were totally fractured. Repairing these - at least to a state where it takes decent, if not perfect, photos - was quite straightforward. One of the fractured supports was reattached with 5-Minute Epoxy. Actual plastic cement would probably be better but you use what you have. ;-) The third was too small to be readily positioned while the glue set and held in place by itself, so it was attached to the 1st Lens Cluster assembly with its normal screw and a drop of 5-Minute Epoxy was added. Then the entire unit was installed using the other two supports. It is hopefully in close enough alignment for government work. ;-) The cracked Zoom Barrel (visible in some of the dissection photos) does not really seem to cause any mechanical or optical problems. This is almost certainly not a perfect or rugged repair, rather more of a quick and dirty "proof of concept". But as they say, if it works, use it. And for now it seems to be working. ;-) And it has been used to take some of the later dissection photos.

      However, this does cause a different sort of problem in that since this lens now works more-or-less, its CPU PCB will not be available to repair #2 if required. That, however, turned out to not really be viable regardless.

    • ID #2 (SN: 20319727): The description said "Does not initialize" which might indicate a broken flex cable, other bad connections, or a bad CPU. However, that is not the case. Zoom is very rough and will not reach the collapsed position. Sometimes the lens will initialize but then autofocus doesn't work and the manual focus ring has no effect, though the focus stepper motor can be heard attempting to do its thing. And indeed there is an optic loose in the back of the lens which may be the Middle Lens Cluster group as its position affects focus. If the camera is pointed at the ceiling and the image will come into reasonably sharp focus. My guess is that this lens was also in an accident and was slammed into a hard surface, front or back, but with no visible damage to the exterior. That would be like the car engine breaking off its mounts but with no external evidence of a collision. Explain that to your insurance company. ;-)

      However, once the Back Lens Cluster was removed, the something literally fell out - a piece of black plastic, though its origin is not yet clear. However, a problem was found after nearly completely disassembling the lens. A slightly mangled spring that provided the restoring force for the focus group did literally fall out. It was supposed to be stretched between a pair of tiny plastic tabs, one on the Focus Lens Group and the other on the Middle Lens Cluster housing. One of those tabs had broken off. Whether that was the original cause or collateral damage is not clear. More to come on that specifically. The solution to that at least was to simply extend the end of the spring that went to missing tab to a handy cross-wise bar nearby. It isn't quite up to Nikon standards but should work. Now if I can only get the thing back together. For this lens, most of the cylindrical parts have 3-fold symmetry except for the orientation of the front label. This it NOT necessarily true of other Nikon lenses. Which is why match marks should always be added if there aren't detailed instructions - it probably has some. However, I did not expect it to be repairable

      But alas, the popped spring was only the tip of the proverbial iceberg. Two of three plastic tabs that rotate the Zoom Barrel with broken off and the third was on its way there. Other bits of plastic were found lodged inside. And with the actual cause unknown, it is unlikely that this lens will ever be completely reassembled. It's one of those situations where something wasn't quite right resulting in a cascade of failures. My guess is that once the spring tab broke, the spring and/or tab piece jammed the lens, and then someone forceably attempted to change zoom breaking those other tabs.

      It's also possible that this is a common problem with these lenses whereby forcing zoom either beyond the stops or due to stiffness from inadequate or gummed up lubrication breaks or bends those tabs. And it's all downhill from there. I have seen at least two other Z DX 16-50mm lenses on eBay with stuck zoom that appear pristine in every other respect.

      The final photos of the dissection show it back together and it now can be set from Collapsed to 50mm (is was jammed originally), But what's not obvious is that the Middle Lens Cluster with Lens Groups 4-6 (including Focus and VR) is not present. The lens might be recognized by a camera since the CPU PCB was reinstalled and attached to the zoom and focus encoder flex cables, but even if it was, the photos would be truly lousy. ;-)

      Since the front of the lens is undamaged, the Front Lens Cluster could be swapped into repaired #1 but that already performs well so there is little point. ;-) And replacement would require nearly total disassembly of both lenses, hardly justifiable if your time is worth anything.

    • ID #3 (SN: 20253184): This appears to be new but without the original packaging. And it works like new.

    Here is most of the dissection of ID #1: Nikon Z Nikkor DX 16-50mm 3.5-6.5 VR Zoom Lens Dissection Web Album.

    • The first half dozen or so photos show this lens in various poses as well as comparisons with the common (non-Z) AF-P DX 18-55mm f/1:3.5-5.6G VR "kit" lens, the Z 24-70mm f/1:4 S VR "kit" lens, and the Z 28-400mm f/1:4-8 VR "superzoom" lens, which has the highest zoom ratio of all the Z lenses.

    • Then the diagram of the internal optical architecture.

    • The next block are photos of lens #1 followed by disassembly of its front section ending with a shot of the repaired lens.

    • And finally disassembly and parts of lens #2.

    • Most of the shots prior to the one labeled: "Nikkor-Z-DX-16-50mm-f4.5-6.3-VR_Front1_Repaired" (around the 40th photo) are of lens #1 and were taken using a Nikkor Z 24-70mm S. They will have a "1" in the name.

    • Those after that are of lens #2 and will have a "2" in the name. Most were taken using the repaired Nikkor Z 16-50mm, lens #1. The remainder were taken with a Z24-70 S because I forgot to switch lenses for those. Can you tell which ones were taken with which lens without checking the metadata? ;-)

    For most of the photos on a white background, the setup used uniform cool white LED illumination on a piece of white paper. Where the broad area illumination and/or the white background poor rendition of glass optics or reflections from metal shims or other surfaces like the CPU PCB, the checkered yellow and white tablecloth ;-) was used and/or a combination of fluorescent and LED lamps for illumination. Post processing may include a bit of sharpening (which usually doesn't do much) and some minor brightness, contrast, and color adjustment where Auto White Balance didn't work so well. For those shot on the white paper which have little or no background evident, no AI was involved in its removal! ;-) And much of this was arbitrary, and please don't whine about the labeling. I know there are inconsistencies. Live with it. ;-)

    Stay tuned for more.

    Nikon Z DX Nikkor 50-250mm f/4.5-6.3 VR Zoom Lens

    This is another mostly plastic lens made in China, but it gets generally good reviews and is relatively light weight. There is currently no repair manual available on-line.

    I have a single sample of this lens:

    • ID #1 (SN: 20021549): The eBay listing had the description: "Focus/aperture not functioning, loose piece in front section of lens, rattle noise when shaken, plastic piece broken off and missing on side." Although it leaves out that zoom doesn't work at all and there are skuffs on the front lens element.

      This is a total basket case all around, but is thus perfect for dissection. ;-) It's just one step short of having been run over by a bread truck. Zoom doesn't work except sometimes by brute force pulling or pushing on the Zoom Barrel (and that doesn't move the Lens Groups as it should when zooming). Something rattles inside which may or may not be the VR Lens Group. And there was a plastic shroud loose inside the front of the lens whose purpose is not at all clear. Oh, and two Nylon zoom guides and a piece of a third were fished out through a hole on on the side of the lens. ;-) Aside from all that it is in perfect condition and may take totally unrecognizable photos when it feels like it. Not just fuzzy, total garbage even if the camera thinks it is optimally focused This probably means that one or more optics are out of position, not that any are seriously damaged. ;-)

    Here is the start of the dissection: Nikon Z Nikkor DX 50-250mm 4.5-6.3 VR Zoom Lens Dissection Web Album.

    Since no real problems with the optics were found after close inspection, the lens was put back together using the partially repaired Bayonet Mount Ring from the Z 24-50mm lens, below. And lo and behold, it actually takes very nice photos, but only when the Zoom Barrel is extended as far as it will go on this (broken) lens. (This was probably true originally but it wasn't tested with the Zoom Barrel at that setting.) Based on the EXIF data from a typical photo, that is 82 mm, which is consistent with the position of the Zoom Barrel. Anything shorter and the camera displays: "Before taking pictures, rotate the zoom ring to extend the lens" and/or will not focus at all. So that is probably where the other lens groups are stuck from the original trauma. Focus works reliably from infinity to a close distance of around two feet, similar to the spec at ~82 mm. The three sets of 1st Lens Cluster shims were NOT replaced because at least one was a different thickness. I didn't bother to keep track of that, assuming that this lens was never going back together. But the difference in thickness is extremely small which shouldn't affect field symmetry very much, and perhaps not detectably at all. But the missing shims would increase the close focus distance by a small amount. I think VR even works, though I can't totally confirm that as my VR test stand isn't set up for Z lenses, and there is also IBIS which might mask any effect of the in-lens VR. But it makes the normal VR sizzling sound when active. ;-) The last photo of the dissection shows the reassembled lens with the Zoom Ring set at around 83 mm just for show. Rotating the Zoom Ring has absolutely no effect on anything as the Zoom setting is monitored by an encoder on the Zoom Barrel itself, stuck at 83 mm, and the pegs that are needed to move the internal mechanism were sheared off.

    It is now probably even good enough for government work as a Nikkor Z DX 83mm f/1:5? lens. ;-)

    But what this means is that further dissection is on hold for now, at least until another sample is obtained. ;-) And the probability of that is rather small.

    A fracture of one or more of the pegs that move the Zoom Barrels due to a mild trauma may be a common failure for the Z 50-250mm lens - There was another one on eBay listed as "For Parts or Not Working" with the photos showing a cracked Filter Ring but otherwise it appeared to be in very good condition. When the seller was asked what else was wrong, they replied: "It will not retract or extend any further. Something is locked up in the mechanism." Well we know what that is! ;( ;-) And yet another eBay listing with photos of a lens that looks pristine but no description of the problem and all the photos show the lens at the same zoom setting. Unfortunately, replacing those pegs is almost certainly not cost effective even for Nikon due to nearly total disassembly required. And that's assuming nothing else has been damaged by forcibly attempting to change zoom on the jammed lens.

    Nikon Z DX Nikkor 12-28mm f/3.5-5.6 PZ VR Zoom Lens

    There is a repair manual for this lens on the Nikon Self Service Repair Website. It has some decent diagrams showing general disassembly and reassembly, but nothing down to the inner core.

    This lens is included here only because it is one of only two Nikon Z lenses currently available in 2025 that has power zoom (thus the "PZ"). The other one is the Nikkor Z 28-135mm f/4 PZ which is almost 10 times the cost of this lens so let's just say that I will probably not even be touching one in the foreseeable future. ;-) Both focus and zoom are "fly-by-wire" in that the Zoom and Focus barrels are optical encoders which send pulses to the lens's micro-brain, and thus they can be controlled remotely and nothing external moves. It is also unique among all the zoom lenses I have tested so far in that there is absolutely NO change in length regardless of focus or zoom settings. The electronically-controlled zoom does take some getting used to in that there is a small but noticeable lag between rotating the Zoom Barrel and the image changing. That's true of manual focus as well (including with AF-P lenses) but it's rarely used.

    I have two samples:

    • ID #1 (SN: 20002414): Near mint cosmetic condition and perfect functional condition.

    • ID #2 (SN: 20024377): Near mint cosmetic condition and perfect functional condition.

    I don't what the greater than 20,000 difference in SNs means. I doubt there were anything like 20,000 of these manufactured or sold. ;-) Perhaps direct from Nikon (#1 in Nikon box) versus from a reseller (#2 in unmarked beige box). They are physically and functionally identical.

    Nikon Z Nikkor 24-50mm f/4-6.3 Zoom Lens

    This is another mostly plastic lens made in China. While not super fast with a relatively limited zoom range, it gets generally good reviews. The format is FX (full frame) and it is fairly small and light, with a overall appearance similar to that of the Nikon Z DX Nikkor 16-50mm f/4-5.6 VR Zoom Lens above, like that one went on steroids. ;-) So it could be a handy lens to carry around. There is currently no repair manual available on-line. Note that this does NOT have VR, which at 50 mm isn't that much of a deficiency, especially if the camera has IBIS (In Body Image Stabilization).

    I have a single sample of this lens:

    • ID #1 (SN: 20111451): Very good to excellent condition except that a couple pieces of the plastic bayonet mount ring were broken off. The seller even provided the missing chunks, though they could never be securely reattached. The lens did still mount and take photos, though there was a small amount of free-play. However, the plastic bayonet mount rings appear to be identical for many of the these lenses, so it alone was replaced with the one from the mangled Nikkor Z DX 50-250mm lens, above. That was easily done in five minutes involving eight screws, without removing anything else including the Camera Contacts unit. (FWIW, there may be compatible metal replacement Bayonet Rings to fit these lenses that should be sturdier.)

    Probably no more to come soon on this lens as it is no longer broken enough to be dissected. ;-)

    Miscellaneous

    Nikon DSLR Doesn't Recognize Memory Card

    This may be specific to the D5x00 DSLRs when attempting to use a brand new SanDisk Ultra 32GB SDHC. The message is "This memory card Cannot be Used. Card is Damaged. Insert another card." Then nothing responds, even the configuration menus, so it cannot be formatted in-camera. And formatting it on a PC using either NTFS or FAT32 makes no difference. A Web search will return all sorts of suggestions. But the simplest is to format the card in a Canon camera. Really. ;-) The specific case here is a Nikon D5200 and Canon SX710 HS. This was not a fluke with a single card but happened on more than one occasion.

    Nikon Electronic Flash Issues

    WARNING: All electronic flashes using xenon lamps have an energy storage capacitor that can hold a high voltage charge for hours to days even with the camera off, the flash disabled, or the battery removed. The 330 V capacitor in a D70 still had more than 250 V on it after at least a day with no battery. Touching the wrong contacts can result in a shocking experience (though probably not a lethal one). But it can kill the camera if it ends up discharging through the electronics. This only matters if disassembling the camera for repair or curiosity and then mostly in areas relating directly to the flash or capacitor. It is not something the user of the camera needs to be concerned with unless the case is damaged, particularly in the areas of the flash or capacitor (whose location depends on the specific camera model). And with the flash cover removed (as might be required to repair one that doesn't pop up), both ends of the flashlamp are exposed. The risk is not necessarily between them as there is an IGBT or a similar electronic switch in series with one side to implement the energy conserving flash control, but between the live contact and other parts of the camera. And that can not only be shocking but kill the camera as well. Discharge the capacitor at the capacitor terminals using a power resistor - 10-15K recommended while monitoring with a DMM to below 1 V or so. Then short across them with clip leads and leave them there for awhile. (Capacitors can recover some charge on their own.) DO NOT just put a screwdriver blade across the terminals as there could be a rather dramatic flash-bang with collateral damage to the shorting tool and terminals. See the document: Electronic Flash Units and Strobe Lights for more details including safety precautions.

    Nikon AF Lens Zoom and Focus Roughness

    If you're used to the silky smooth operation of a classic Nikon lens like those for Nikon film SLRs, it will be a bitter disappointment to use a modern Nikon DSLR zoom lens. Lenses like the 50 mm f/1.4 "standard" lens or 43-86 f/3.5 zoom lens were works of art in comparison. They were mostly made of machined aluminum and well lubricated. Many samples 40+ years old still perform like new.

    Modern lenses are much more sophisticated and no one would want to go back to the fully manual older ones, but silky-smooth operation is not one of their features. And it's easy to see why. Most of the moving parts are made of plastic and a zoom lens has many of them. For example, see Major Moving Parts of Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens. These all move when changing zoom or focus. The three cylinders at the top of the photo reside nested and rotate or slide with respect to each-other with a large surface area in direct contact. The center one is made of anodized aluminum with precisely milled slots that determine the required movement of multiple lens groups with respect to each-other when zoom is adjusted; the other cylinders are formed or molded plastic. The straight slots in the upper-left (outer) cylinder guide those moving parts that must not rotate. Pegs or rollers (without ball bearings) restrict their movement to the AND of the slots in the upper left and the other cylinders, but also add friction. Some parts reverse direction as the Zoom Barrel is turned, adding additional friction/resistance at that point. It's all rather intricate and I bet Nikon has a really nifty CAD package for zoom lens mechanical design. ;-)

    As an example of a common much larger lens, see the diagrams in Nikon AF-S DX Nikkor 18-200mm f/3.5-5.6G VR Zoom Lens showing Lens Group Positions at 18 and 200 mm. Lens Group 3 and the VR assembly move together, but those and all the others move relative to one-another and relative to the lens structure attached to the Nikon F mount.

    Even on a brand new lens, there is detectable roughness and varying resistance over some parts of the zoom range. Over time, the lens will be exposed to dust, moisture, and contamination either from normal use or from being tossed in a storage bag, it gets worse as there are no real seals. And plastic is subject to wear. The good news is that for the most part, none of this makes any real difference in picture taking performance. That is, until the thing seizes up completely or falls apart. :( ;-)

    But if the lens is dropped or whacked, parts like those pegs can get broken off or may dig into the tracks with varying degrees of damage. In minor cases, the roughness will just become worse but with enough trauma, major functions will stop working. When considering the purchase of a used lens, carefully check autofocus, manual focus, and vibration reduction, as well as for correct operation of the aperture at all zoom settings. Don't accept a lens where manual focus doesn't work reliably even with a discount (as I once did) because the seller said no one ever uses it. While that may be partially true, unreliable manual focus can be a symptom of more major problems. One thing that is often broken on used lenses though is the Lock button if there is one, used to secure the lens in a compact state for storage. The internal lip that the button engages is made of plastic and users often attempt to twist the Zoom Barrel without realizing it's locked, so that lip gets damaged and the button non longer works properly. That alone is probably not sufficient reason for rejecting a lens - but perhaps it may be leverage to negotiate a discount! While Lock may not work or work well, the end-stops for the Zoom Barrel should not be affected. But this should be confirmed as bad things may happen on some lenses if the Zoom Barrel is rotated beyond the normal range.

    Mechanical versus Electronic Shutter Complexity

    For all except camera geek types, this is probably just in the "that's interesting department". ;-) Mechanically-controlled shutters - both leaf and focal plane type - are designed along the lines of precision time-pieces with springs, gears, cogs, escapements, and levers that open and close the leaves or blinds. But whereas clocks are supposed to run at a fixed rate, shutters typically have 10 or more speeds. Electronically-controlled shutters use a pair of solenoids to determine the timing based on signals from a microcontroller. As an example, see: Comparison of Mechanical and Electronics Focal Plane Shutter Complexity. The Copal Square S shutter on the top is from a Nikon Nikkormat FTN 35 mm film SLR; the one on the bottom is from an older Nikon D80 DSLR. (The photos have been scaled so that they are approximately the same size independent of the FX and DX formats.) To fine tune the mechanical shutter requires the adjustment of the torque provided by some springs, the position of specific parts, and even the selection of slightly different parts based on actual timing measurements. And even then, the actual shutter speeds may only be accurate or repeatable to within ±10% on a good day. For the electronic shutter, it is just firmware code which could be optimized automatically after assembly. ;-) Shutters in other DLSRs where control of the sensor itself is NOT used to determine exposure at any speed would be similar. For those cameras where the sensor is used as the high speed shutter like the D70, they would be even simpler. In principle, there should be no need for any mechanical shutter in a DSLR or mirrorless camera but for practical reasons, this is rarely - of ever - the case. But point-and-shoot cameras generally do NOT have a mechanical shutter of any kind.

    Copal Square S Focal Plane Shutter

    The original Nikon F used a horizontally-moving focal plane shutter with fabric curtains. The fastest flash sync was 1/60th of a second. The Nikkormat FT/N use a vertically-moving Copal Square S focal plane shutter with metal "Venetian Blind" panels with 3 slats each. It can flash sync at down to 125th of a second. The Copal Square S shutter is an example of the state-of-the art in mechanical shutter design. It is described as a workhorse which really doesn't break, though as with any mechanical system, may require cleaning and lubrication after a half century or so. However, it is common to find these dating from the 1970s or earlier in perfect operating condition. At first glance, the mechanism might appear to be too complex to have ever been designed by humans. Think of a mechanical pocket watch with 11 speeds. But it evolved from or in parallel with leaf shutters that have similar timing requirements.

    See the Web Album at: Copal Square S Focal Plane Shutter Mechanism. (The Web Album photos are scaled to fit within 1024x768 pixels but the full size originals have the name under the thumbnail with a ".jpg" added.) The first 4 photos are of a beat up Nikkormat FTN in various stages of disassembly starting with most of the pieces of the lens mount in place to revealing the Copal Square S shutter in situ. These are followed by closeups of another similar shutter. The primary difference between them is the use of a less expensive Nylon gear for the speed select compared to the highly polished brass one, and some slotted head screws in place of Philips head screws. Since there is no real stress on that gear, cheaper is just fine, thank you. ;-) My black dot on the white gear lines up with the post for the 1 second setting. In the interest of full disclosure, I have swapped the gear and screws to make the separate shutter mechanism more photogenic. And in the interest of expediency, the screws that secure the body parts have been left off. ;-)

    Two manuals relating to Copal Square S Shutter repair are known to be available on the Web and hard copies may be purchased on eBay and elsewhere. Both Copal Square S Shutter Repair Manual and Copal Square S Shutter Repair Guide are interesting reads, but they may not enable you to be able to do much in the way of repair. The first one does have a 75 (!!) step procedure with diagrams for assembling a shutter. ;-) Aside from the intricate nature of these mechanisms, special jigs and instruments are required for some of the procedures. However, cleaning and lubrication of specific parts may be possible. This will involve the use of solvents like alcohol or naptha along with an ultrasonic cleaner if available, followed by lubricating specific bearing points and surfaces ONLY with the tiniest speck of special oil or grease as appropriate. A shotgun approach of simply sprayng it with degreaser and adding oil anywhere that looks appropriate will likely result in a nice paperweight. DO NOT even think about allowing WD40 or anything similar near a precision mechanical device like this! ;( ;-) A Web search will turn up suitable procedures but take them all with a grain of sand.

    Control of the shutter bears similarity to that of mechanical leaf shutters, but it needs to determine the timing of the pair of blinds rather than opening and closing a set of leaves. For the Copal Square S There are three (3) regimes of timing:

    • 1 to 1/4th second: Timing is determined by an escapement provided by the "Star Wheel" and "Pallet" with the 2nd Gear driving the 3rd Gear to step up the gear ratio. (The 2nd Gear rotates a fewer number of turns.) The escapement serves a similar function as in a mechanical clock, but at a much higher speed with the Star Wheel in place of a balance wheel or pendulum in essense provides a more-or-less fixed rotation rate for the gear driving it somewhat independent of torque and is the cause of the buzz heard on slower shutter speeds. The shutter speed here is then determined by how far the 2nd Gear is programmed to rotate before the shutter closes.

    • 1/8th to 1/125th second: Similar to above but the 2nd Gear drives the Star Wheel directly (via an idler gear). 125th second is the highest speed where the shutter opens fully and thus supports X-Sync for electronic flash.

    • 1/250th to 1/1,000th second: Timing is determined separately and does not involve the escapement. The shutter opens only part way as the blinds move from top to bottom with a window of 50%, 25%, and 12.5% for 250th, 500th, and 1,000th second, respectively.

    And as a matter of interest, operation of the shutter in a fully mechanical SLR and specifically the Nikkormat is as follows:

    1. The film advance lever cocks the shutter via a rack gear at the bottom of the camera, cocks the mirror mechanism via a lever linked to the rack gear, and advances the shot counter.

    2. Pressing the shutter button triggers the mirror to flip up.

    3. When the mirror reaches the fully up position, it triggers the actual shutter to open.

    4. Once the shutter has closed, the mirror returns to the down position.

    For the "B" setting, everything is the same except that a tab on the shutter linkage prevents the shutter from closing until the button is released. The actual shutter speed is probably forced to 1/1000th second so closing would not be delayed no matter how quickly the button is released. The Nikkormat doesn't have a "T" setting, but for that operation would be similar but there would be a simple escapement that would require the button to be pressed a second time to close the shutter.

    Optical Materials used in Nikon Lenses

    Until I started to dig deeper into the construction of these lenses, I had always assumed they used individually ground and polished glass optical elements. Sure, inexpensive pocket cameras have always used plastic optics, but Nikon-branded DSLR lenses? Really? ;-)

    It turns out that a variety of types of glass and plastic may be used and the optical elements may be either ground and polished or molded. Sometimes the lens specifications will include some information on the material thought probably NOT the fabrication method if the Marketing Department thinks it will help sales. For example, Extremely low Dispersion Glass (ED Glass) and aspheric are pointed out in the info for lenses like the AF-S DX Nikkor 18-55mm or 18-200mm. They probably won't state anything if plastic. ;-) If not specified, the material can be any either common optical glass (BK7, crown, flint, etc.) or plastic. Aspheric elements are probably molded since individually grinding and polishing them would be cost prohibitive.

    There is no easy way to determine the material and fabrication method non-destructively (or at least without some damage) on an intact lens as they appear identical. But even if the lens is disassembled into the individual lens groups it's a challenge. Glass is several times more dense than plastic so the weight of a lens group can be a tip-off, especially for the larger ones. Ground and polished lenses will generally have frosted edges while molded ones will have smooth lips and perhaps even tabs. But the overall appearance of the individual lens elements is essentially identical in terms of surface finish and AR-coating.

    Diagnosing Nikkor AF-S Autofocus Problems

    Nikkor AF-S lenses have a reputation for reliability problems. However, this may be undeserved at least in my experience. I've acquired some AF-S lenses in fairly dreadful cosmetic condition that worked just fine. And where there were focus problems, they have not been due to the SWM or related parts. However, these are more complex than the later AF-P lenses, both mechanically and electronically. The symptoms may be a total failure to focus, movement of the focus more likely in or out, or erratic behavior.

    Some possible causes are:

    • Auto focus control: The sensing of correct focus is done in the camera and not in the lens.

      Diagnostics: Test with another AF-S lens. If that also fails, the camera is likely at fault.

      All cameras tested that would turn on worked correctly with AF-S lenses. Dead cameras don't count. ;-)

    • Auto/Manual (A/M) Focus switch dirty or defective: This is certainly possible as the switch does two things: (1) it completes a circuit to enable the focus motor and (2) it mechanically engages the gear train so that it can move the focus ring. The switch could be dirty or defective, or a wire may have come off.

      Diagnostics: Cycling the switch back and forth a few times may clear any contamination. But on lenses with the small SWM, this also engages and disengages the gear train, so that can result in the gears moving a bit with respect to each other and avoiding a damaged tooth or becoming unjammed. Set the switch to M and confirm that the focus ring moves smoothly by hand. Also confirm that there is normal free play in the focus ring with the switch set to A. This should be a few degrees of rotation or around a mm at the perimeter. It should not be tight with no free play. Then listen carefully for any sound while the camera is attempting to focus. If present, there may be a mechanical problem in the gear train. If there is none, then it's an SWM or electronics problem.

    • Stripped or worn gear(s): Not all AF-S lenses have any gears. The AF-S DX Nikkor 18-70mm f/3.5-4.5G ED IF zoom lens uses a ring SWM which is directly attached to the focus ring, so these comments do not apply. But most like the AF-S DX Nikkor 18-55mm f/3.5-5.6G VR and VR II zoom lenses have 4 plastic gears which are subject to wear. Some may be damaged by attempting to rotate the focus ring with the A/M switch set to A.

      Diagnostics: In a quiet room, listen for mechanical noise when the lens should be focusing. If the SWM is seized, there would likely be none as the drive frequency is beyond the range of human hearing - typically between 25 kHz and 300 kHz, though it might be audible to your pet bat. ;-) If you can hear anything which sounds similar to the sound made during normal focusing but the focus ring isn't moving, a mechanical problem is likely.

      See the info above on lens ID #4.

    • Autofocus gets stuck over part of its range: This is a strange one and applies to lens ID #4. AF works fine up close - say a foot or two and back and forth within this range. And focusing out - going from close to far also seems to work to infinity. But attempting to focus closer when it is at more than a few feet results in no action but slight noise as though it's trying. The camera will still beep if the focus *happens* to be correct, but the focus ring won't move. The zoom setting doesn't matter very much. Once it gets into that state, the switch has to be set to M and the focus ring moved closer. But that is quite consistent so I now rather doubt it to be a mechanical gear problem.

      Diagnostics: Cycle the A/M switch and move the focus ring. Determine if there is focus distance or range of distances where autofocus works consistently. and if there is a preference for focusing in or out.

      On one Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II zoom lens (my ID #4), AF was intermittent and just cycling the A/M switch sometimes helped. But rotating the focus ring with it set at M always seemed to allow the lens to focus correctly for several shots. There was no binding or detectable resistance so this suggests a damaged gear. When it stopped working, repeating this would get it to recover. Since the gear ratio is so high and the motor and immediate drive gears are disengaged with the A/M switch set to M, the only gear likely to be relevant is the ring gear on the focus ring. The pinion gear that engages it goes though more than one revolution and all the others go through multiple revolutions over the focus range. And when rotating the focus ring manually, it also rotates the pinion gear. Chipped or damaged teeth would be detectable. Likely causes are damaged or dirty focus encoder or tachometer. For more info, see the section: Autofocus only Works Over Limited Range on Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR II Zoom Lens.

    • Focus will not change unless torque is applied: In essence, the SWM is not self-starting either CW or CCW but if nudged, will move reluctantly in either direction. A likely cause is that one of the two phases that drive the SWM is low, or more likely missing. Just like a split phase induction motor with a bad winding. There is a ferrite component for each phase driven by a transistor circuit. A single bad part can result in these symptoms.

      Diagnostics: Test the discrete semiconductors near the ferrite components on the POW PCB for shorts. On one lens with these symptoms, two pins were indeed shorted on the SO23 drive transistor for one of the phases..

    • Silent Wave Motor (SWM) damaged: This is the ultrasonic motor that moves the focus ring directly or via a gear train. They are not sealed, operate on the nanoscale, and are driven with a pair of high frequency high voltage phases in quadrature. The typical drive voltage is 240 V p-p at 70 kHz. The SWM is a purely capacitive load but it doesn't take much to interfere with correct function. Dust or contamination of the moving surfaces could result in stiction or excessive wear. Moisture on the electrical contacts may short out the drive signals. If it is known that the lens got wet, DO NOT attempt to use it until there has been time for it to dry completely. Originally I had assumed a failed or erratic SWM to be the most likely cause of autofocus problems with AF-S lenses given these potential points of failure. This may still be true, but now I'm not so sure based on testing of several faulty AF-S lenses. Where a repair manual for an AF-S lens is available, there is always a caution NOT to touch the SWM in the vicinity of the stator slots. Presumably finger contamination can cause failure. So it's not surprising given the lack of any real sealing on these lenses that environmental contamination can as well.

      Diagnostics: If an oscilloscope is available - almost any type, even an antique - it's simple to check for the presence of drive signals, though determining if both are present might be challenging. All that's needed is a simple sense coil of a half dozen turns with a diameter of around 1.5 inches. The sensitivity with the typical AF-S lens is very roughly 10 mV p-p/turn. It doesn't have to be beautiful. ;-) Using a 10X probe but no other termination should be adequate. For all the lenses I've tested, a good place to position the coil is directly underneath the lens slightly near the camera. But feel free to experiment. ;-) With the scope's vertical sensitivity turned up, there should be a very distinct signal while the lens is attempting to focus, and for some cameras, possibly even after it had succeeded or given up. What is probably being detected up are the fringe magnetic fields from the ferrite components on the SWM driver PCB. A lack of this signal would probably indicate an electronics problem. See the sections on the specific AF-S lens models for details on testing. It's straightforward if fiddly to remove only the Fixed Shell on some of these lenses so that the innards can be probed while on a camera.

      On one Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR zoom lens (my ID #1, the lens documented in the section: Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens), AF was totally inoperative and there was obvious damage stator and rotor of the SWM as can be seen in Nikon AF-S DX Nikkor 18-55mm f/3.5-5.6G VR Zoom Lens Autofocus Drive Assembly and Piezo Motor Parts.

    • SWM autofocus not doing anything: The SWM may just be stuck. ;-) (This is not likely to apply to the stepper motor in AF-P lenses and regardless, getting to the stepper motor requires extensive disassembly.)

      On a lens that is otherwise functional and recognized by the camera, possibly not having been used in a long while, the stator may have stuck to the rotor of the SWM. If repeatedly attempting to focus does nothing and the switches, weak battery, and menu settings have been ruled out, it's possible the SWM is just lazy. The first test if technically savvy would be to check for the SWM drive signals using a coil of wire and oscilloscope as described elsewhere in this document. If strong drive signals are present, attempt to rotate the focus ring while autofocus is active. Don't go to excess as there is a risk of stripping gears, but some modest torque may free it up. If it does move but in either directly during focus, one of the high voltage drive phase signals may be missing. If it only moves in one direction, there may be contamination on the rotor-stator interface surfaces but both phases are probably present. If the focus ring cannot move at all, it is sometimes possible to access the SWM through the switch cover and prod the rotor with something pointy like a jeweler's flat blade screwdriver WITH THE CAMERA TURNED OFF taking extreme care not to touch anything but the edge of the rotor. If the rotor can be moved at all, autofocus may then work and should be exercised. Depending on the cause, this may be a permanent fix but the symptoms if there is significant contamination or damage. Use of a drop of cleaner/degreaser may help but don't use a spray as there could be permanent collateral damage. Just a drop on the interface between the stator and rotor and then exercise it. Else total stripdown of the SWM - or replacement - may be required.

    • Focus encoder: Any contamination on the encoder strip can result in all sorts of strange behavior.

      This would most likely require disassembly and inspection of the encoder strip and brush assembly.

    • Focus tachometer: For those with an optical tachometer like the AF-S 18-55mm VR, this would probably result in an inability to focus at any distance. For those with a magnetic tachometer like the AF-S 18-55mm VR II, it would be possible that partial erasure of the magnetic strip could result in problems over only part the range like the lens described above.

      This would most likely require disassembly, inspection, and electrical testing.

    • Driving electronics faulty: The SWM requires a two phase high voltage drive signal to operate. The relative phase determines the direction of motion. If either or both of these are missing or weak, the motor won't do anything. It may be difficult to confirm that both signals are present, but a lack of anything would confirm an electronics problem.

      Diagnostics: Similar to those for the SWM, above.

      Drive failure is not very common but has been seen where one phase was missing or weak so the focus ring would try to move but needed help. ;-) More likely is that the surfaces of the SWM itself have become gummed up from environmental issues or prior attempts at repair.

    Nikon Silent Wave Motor (SWM) Disassembly

    The following applies to the compact SWMs like those used in the AF-S DX 18-55 mm "kit" lenses. (The full diameter SWMs in those like the AF-S DX Nikkor 18-70mm f/3.5-4.5 ED IF lens are secured by the overall lens focus mechanism.)

    Since there are no user seriveable parts inside ;-), this is probably only justified to attempt cleaning of a gummed up SWM, or for curiosity.

    Take some photos to record the arrangement of parts.

    The motor is held together with an itty-bitty C-clip at the non-gear end. That needs to be popped off carefully so as to not have it go pinging across the room to be lost forever. You won't find a replacement in your junk box or Home Depot!

    Then the shaft with spring and gear will slide out from the disk that mates with the fingers of the ultrasonic transducers. The mating surfaces must be clean and free of any lubrications. It's metal-metal contact. If it is gummed up, carefully clean with alcohol or acetone avoiding getting aolvent anywhere other than the mating surfaces. Reassemble in reverse order.

    Lithium Ion Camera Battery CPR

    WARNING WARNING WARNING: Perform this stunt at your own risk! And please read up on what a Web search returns for something along the lines of: "Lithium ion camera battery zero volts". And we will not be responsible for damage to your ego, anatomy, or the Universe that may result. Having said that, the procedures described below should be pretty safe, though it may not be fool-proof or safe from fools. ;-)

    The following applies to the type of Lithium-Ion (Li-Ion) battery packs found in Nikon (and other) digital cameras. Don't try this on your Tesla™. ;-)

    CAUTION: This remedy ONLY applies to a battery pack whose terminal voltage reads exactly 0 V. It CANNOT be used with individual cells that still have a measurable voltage, individual cells that lack a protection circuit. or a battery pack where one or more cells are dead and the terminal voltage is non-zero but never reaches its rated voltage even after an extended time on a compatible charger.

    When the type of Li-Ion battery pack found in digital cameras discharges below its useful minimum voltage, not from normal use but usually from a prolonged period of inactivity like YEARS, the internal Battery Protection Module (BPM) kicks in so the pack's output voltage may measure zero volts even though internally there is still some charge remaining on the individual cells. This is to prevent the battery from being discharged further by connecting it to a load which can result in permanent damage. Normally, a low voltage cutoff circuit in the camera (or other device) will shut off before the BPM activates so there will still be a non-zero battery terminal voltage. But if the BPM has disabled the output entirely, smart chargers may also refuse to recharge the pack unless they have a 0V activation feature.

    The solution is to apply a current-limited voltage to the battery terminals to reset the protection circuit. Plus-to-plus, minus-to-minus, just like jump-starting a car. But unlike a jump, this is simply to reset the BPM, not to actually charge the battery. That should be left to the appropriate charger. A variable DC power supply with voltage and current readouts is best but an inexpensive easy to construct alternative power supply can also be used. More below. As the voltage is increased starting from 0 V, initially there will be little or no current, but once the BPM has reset, the battery will draw current and it will then retain the voltage if the input is reduced or removed. If successful, the measured output voltage will then be 2/3rds or more of the rated voltage. The battery can then be put on a compatible charger and should respond normally. Some so-called "OV" chargers will deal with the reset auto-magically, but probably not those from Nikon.

    Having said all that, this is not rocket science. ;-) A simple BPM reset device can be constructed from almost any DC power supply with an output that is current limited to order of the battery's mA-hr rating/hr. So for a pack rated at 7.4 V, 1,000 mA-hr, a 12 VDC wall adapter with a 10-15 ohm power resistor for current limiting should be acceptable. But don't omit the resistor - there may be a non-resettable fuse inside the pack which could blow from even momentary excessive current. And there is a risk of fire and explosion from REALLY high current. Thus, don't try this using a car battery or your arc welder as the power supply. ;( ;-) And if the pack doesn't recover decent voltage after a couple of shots, it may be too far gone.

    If you are curious as to how it typically works, see: Analog Devices 4.5µA Li-Ion Battery Protection Circuit. A typical Li-Ion battery pack will include a BPM which is functionally similar. For this specific BPM, CPR current will flow through the substrate diode of the MOSFET (SW1) from (right to left) to increase V_BATT just enough until the circuit resets. That will typically take relatively little current.

    CPR was successful on several EN-EL9 batteries that came with a low mileage Nikon D40X DSLR which had probably been sitting around unused for 15 years or more. The EN-EL9 have 2 cells and is rated at 7.4 V, 1,000 mA-hr (for the original version, up to 1,080 mA-hr for the EN-EL9a and EN-EL9e). They initially all played totally dead with a terminal voltage of exactly 0.00 V and this did not change even overnight on the Nikon MH-23 charger. An unregulated variable DC power supply with a built-in voltmeter was used to increase the voltage across the battery terminals just to the point where it started drawing current indicating that the BPM had reset. That point was easily found with this unregulated power supply since then the voltage dropped and changed more sluggishly with respect to the voltage adjust knob due to the load. The batteries were then put on the MH-23 charger. After 15 minutes or less, each had enough juice a Nikon D40X to power on. Full charge was reached in around an hour. Only time and use will reveal if they will hold a charge and have decent capacity. So far, those that have been used them to test D40X and D60 DLSRs, have held their charge over several months. I would assume that the reason the needed to be reset was that they were unused for a couple of decades. ;-)

    Press Shutter Release Button Again Error

    This issue is common across many of the Nikon D-series DSLRs (if not more). It will probably occur after taking a photo, or when power is turned on. And usually, pressing the shutter button will have no effect on clearing the error. After this occurs the first time, it will probably occur again even if can be cleared. Affected models include the Dx0, D3x00, and D5x00. Which is just about all of them.

    There can be several causes but all relate to the shutter/aperture mechanism being unable to cycle properly either due to gummed up lubrication or a cracked pinion gear on the aperture/shutter motor. The latter is so common that there are hundreds of listings on eBay for replacement gears as well as YouTube videos with the installation procedure. Check them out. While popping a new gear onto the motor shaft is easy, getting to it involves extensive disassembly. For an older camera like the D40, it is probably not worth the trouble and time except out of curiosity and boredom. ;-)

    Depending on the model, it may be possible to lubricate a different gear (typically made of red plastic) accessible by removing only the bottom plate (a half dozen or so screws). Just rotating this gear with a fingertip may free up the mechanism - once! But it's unlikely to be a solution. If it seems dirty or gummed up, careful cleaning may help. And even if this appears to work at first, the issue may still be the motor gear.

    Sick Nikon Z7 Mirrorless Camera

    This was acquired on eBay "For Parts or Not Working" with a description that it was dropped in water. Normally I would steer clear of anything like that but the photos showed no evidence of water infiltration or that it had been steam-cleaned ;-) and it was otherwise in extremely good almost pristine condition.

    Here is the exact description from the seller:

    *This camera does not turn on*

    Camera was dropped in water and does not turn on. Function light turns on when battery is inserted but screen does not turn on. Use for parts.

    Initial observations

    The Z7 is indeed in near perfect cosmetic condition with just a small damaged area on the rubber grip, perhaps caused when it was dropped.

    While the camera arrived with very serious problems, that description is not entirely accurate. In fact, the camera *does* turn on, but usually only if the battery is installed with the power switch in the On position. In that state, menus can be accessed and settings can be changed, and most controls are functional. The main or viewfinder LCD can be selected and the view through the lens from the 45MP sensor is displayed, though the view is unstable with slightly fluctuating intensity and there is an audible clicking sound (more on this below). However, Z lenses are NOT recognized at all so focus (auto or manual) does not work and only those shooting modes that do NOT require interfacing with the lens can be used. (The others like "P" are disabled.) As will be seen though, that isn't the end of the world.

    Whether this behavior was not observed by the seller because they never installed the battery with the power switch in the On position or that the behavior has somehow changed between their testing and it arriving here is not known. If it did indeed get wet and has dried out since then, it's possible some parts could have come alive.

    The meaning of the seller's statement: "Function light turns on" is not clear, but it probably refers to the memory read indicator. With an XQD card installed, that LED does come on momentarily as is normal. (In the non-sequitur department, one of the annoying things about the Z6 and Z7 are that they do not accept common SD cards, only the higher performance and expensive XQD cards. That makes sense for video but not for stills. The Z6ii/z6iii and Z7ii have dual card slots so either type can be used.)

    And it will shoot. In M (Manual) mode, the shutter speed may be selected, uh, manually and the exposure of the resulting images does track that setting. However, not only does AF not work, but the manual focus on Z lenses using the ring on the lens is also inoperative. In both S (Shutter Priority) and A (Aperture priority) modes, the shutter speed will adjust based on the required exposure, though in both cases whether the aperture is whatever it was set at last time the Z lens was used on a working camera or simply defaults to one extreme or the other (probably wide open) is not known.

    My suspicion was that the lens isn't getting power along with portions of the circuitry responsible for storing the Menu data (except for Date and Time which are presumably in a separate RTC chip or something). Perhaps a fuse blew during its aqueous encounter. I did compare voltages on the Camera Contacts to the lens with those on my working Z6III (with no lens attached) as described below. But no real conclusions could be drawn from that.

    Observations prior to partial recovery

    (Some of this is redundant):

    • The camera will reliably power up only if the battery is installed with the camera turned on after having been removed for a few seconds or more. The one known exception is that USB to a PC may wake it up at random with the battery installed.

    • In that On state, most buttons work as expected and the Menus may be accessed and will behave normally. But any settings that were changed will be lost when the camera is powered off. Both the main and viewfinder LCDs display normally, and it will shoot subject to the limitation that it doesn't recognize any Z lenses. The power switch can be used only to turn the camera off, at which point the top LCD display may remain on (and and possibly bright!) but nothing else will be active and the battery must be removed and replaced again before it will come back alive.

    • Z Lenses are not recognized and therefore the camera is unaware of the lens parameters. Focus (both auto and manual) is inoperative and the lens format (FX or DX) is not known so it defaults to FX and thus the image from a DX lens may vignette over most or all of a zoom lens's zoom range. FX or DX can also be selected in the Photo Shooting Menus but the setting will be lost when the camera is powered off.

    • AF-S and other F-Mount lenses having a manual focus option may be used with an FTZ or FTZ II adapter in which case A (Aperture priority) mode will work and automatically adjust the shutter speed, though the aperture will not change. S (Shutter priority) mode behaves identically for some reason. Manual mode may also be used with manual control of shutter speed.

    • There is usually a constant jiggling noise along with random small variations in brightness but his turned out to likely be lens-related. Testing up to this point was done using a Nikkor Z DX 16-50mm f3.5-5.6 VR lens.

    • USB-C is occasionally recognized and will then connect to a PC normally with the power switch in the ON position even after it had been turned off and there would normally be no response of any kind from the power switch or any button. And sometimes the power switch will work to turn the camera on and off but only with USB plugged in. Or the camera may just wake up after a random delay with USB plugged in. Perhaps it's getting enough power through the USB-C cable to keep something alive even though it's attached to a wimpy USB hub. But only occasionally. In short, its behavior with USB is strange and flaky. Go figure. ;-( At first the connector was suspect but close inspection appears to show it to be clean and undamaged.

    • Turning the camera off after being alive will result in the following message on the LCD: "Wireless transmission will continue. To suspend transmission, select "Off" for "Send while Off". That is a Menu setting but is grayed out, and even if it could be changed, the new setting would be forgotten when the battery was removed.

    • The default state is probably NOT a total reset but more likely whatever it was before the "event". Changes just do not make it into non-volatile memory. For example, the live view comes up with grid lines and a histogram, and it thinks wireless transmission is enabled as noted above.

    • Attempting to reset all settings to the factory default via the Setup Menu hangs with the message: "Resetting all settings to default values". Everything is then inoperative including the power switch. The battery must be removed and replaced for the camera to do anything.

    • Attempting to update the firmware from the memory card hangs. (At least it didn't brick the thing!) The cause is likely the same as the Settings Reset hanging.

    A Nikon EH-7P AC Power Pack is on order to see if behavior is any different than with the battery.

    Some progress

    The EH-7P arrived. The camera will NOT power on (with or without the Power switch) using only the EH-7P but I don't know if that is to be expected.

    • If the EH-7P (USB-C Adapter) is powered on after the battery is installed with the power switch in the "On" position, then the Power switch can usually be used to turn the camera off and then back on consistently. (Getting into this state doesn't always work for some reason, perhaps a matter of waiting long enough.) Further, when that works, Menu items can be changed and they will be remembered even after all power is removed.

    • It was even possible to update the firmware, though that didn't appear tp make any difference in behavior. So some memory is now working but only with the USB-C power.

    • Resetting to the factory default settings (which used to hang) also now worked. This eliminated the Network message when shutting down AND now the power switch works to turn the camera on and off with only the battery installed.

    • The +/-, ISO, and Video/Still selector switch do not do anything. The REC button only asks to select a non-CPU lens but will not record (Which means Video is not being selected since that is the correct response for Stills). Perhaps these share the same ribbon cable or power, which is faulty. However, the DISP button which is in the Video/Still selector switch works normally. Some other buttons respond to the extent that they will cancel MENU, though it's not clear if they are doing what they are supposed to.

    • And in the "well, that's interesting department", I just noticed that 2 screws are missing from the bottom plate.....

    So except for the fact that CPU lenses do not work (Z or F with adapter), much more seems to be functional. However, Movie recording does not do anything and some adjustments using the front and back wheels at the top of the camera don't seem to function correctly. The question then becomes: "Is there some final single corrupted setting that is preventing the lens from functioning?".

    Semi-manual photography

    And the camera does shoot and save photos to an XQD memory card and can upload them to a PC via USB. Based on the EXIF data, the shutter count is around 76K which is fairly young for a Z camera, which has an expected ilfe of around 200K clicks.

    Of course without electronic focus or even manual focus on Z lenses, photos are dreadful. Older F-mount lenses with a manual focus option may be used with an FTZ or FTZ II adapter. One of the menus enables entering parameters for non-CPU lenses (though that isn't essential). Manual focus would then be usable though the aperture would probably be stuck wide open, which is where it would have likely been last time when attached to a working Z camera. This has been confirmed using an AF Nikkor 35-70mm f/1:3.3-4.5 lens with the camera set to M. The shutter works as expected; the aperture is wide open. This lens has an option for totally manual aperture but the camera (or more accurately, the FTZ adapter) keeps it wide open. If the aperture lever on the lens were removed, then aperture could be set.

    But there are F-to-Z adapters that function only as spacers - there is nothing inside to control aperture or pass signals to the lens. With one of these, (a Fotasy NK-N/Z, $13 on eBay), the camera behaves perfectly in M mode and with decent exposure control in A mode. And interestingly, the jiggling and brightness variations have disappeared, so perhaps they were caused by an unhappy Z lens or the camera being unhappy with the Z lens. Though how the Z lens was getting power at all based on the measurements below is not clear.

    In addition to some really old fixed focal lenses lenses totally manual lenses that were for my Nikon FTN and Nikkormat FT cameras, I bought a couple of somewhat newer FX format zoom lenses, an AF Nikkor 35-70mm f/1:3.3-4.5 and an AF Nikkor 35-135mm f/1:3.5-4.5. These are of course now dirt cheap on eBay. ;-) Both can be used with the F-Z adapter. It's not really even necessary to enter the lens parameters. Focus adjustment is best done using electronic Zoom on a tripod with a remote shutter release to minimize vibrations since when zoomed in everything jiggles and it's not clear if the IBIS (In Body Image Stabilization) is working (or should be working). But with care, Touch Shutter is acceptable. While focus would be most accurate with the aperture wide open, it works well zoomed in at whatever aperture is desired. The image on the LCD accurately reflects what will be in the photo.

    As a test using the Fotasy NK-N/Z F-Z adapter and AF Nikkor 35-70mm f/1:3.3-4.5 zoom lens, this Z7 was used to take all the photos of sad looking lens in the Nikon AF-P DX Nikkor 10-20mm f4.5-5.6G VR Zoom Lens Dissection Web Album, which is only partially completed. So the thing does take decent photos, even if it is a bit annoying to use manual settings like in the good old days before auto-exposure and auto-focus. ;-) But for "set-piece" still life photos like this, it really isn't that annoying. And they are actually pretty decent.

    Electrical measurements

    Here is a comparison of resistance and voltage measurements at the lens contacts on the camera (with no lens attached) for the healthy Z6III and sick Z7. All readings are with respect to the silver lens mount ring. "R+" is the resistance with the positive lead of the DMM to the contact; "R-" is with the negative lead. The resistances were measured with the battery removed; the voltages were measured with the battery installed and the Camera On. The numbering starts at the top-left facing the front of the camera. Errors are possible:

                   Healthy Z6III               Sick Z7
     Pin         R+      R-      V        R+      R-      V      Comments
    -----------------------------------------------------------------------------
      1        495 K   486 K   1.75 V   167 K*  40.7 K  1.6 V*   Enable to lens?
      2        482 K   482 K     0      4.84 M   Inf      0
      3          0       0       0        0       0       0      Common GND
      4        155 K   2.18 K    0      1.53 K  139 K*    0
      5          0       0       0        0       0       0      Common GND
      6         26 K   8.13 K    0      470 K   466 K     0
      7       1.57 M   3.12 M    0      2.45 M  1.95 M    0
      8       0.83 M*  1.00 M    0       1 M    0.99 M    0
      9       22.7 K   26.9 K    0      470 K   463 K     0
     10       21.8 K   25.7 K    0      470 K   463 K     0
     11       21.8 K   26.3 K    0      470 K   463 K     0
    

    * indicates that the voltage or resistance unstable and changing as though a capacitor was charging and finally settled down at approximately the value shown.

    The only pins whose functions appear to be known with certainty are 3 and 5, Common GND. The most striking difference between the two cameras is that the healthy Z6III has a very stable voltage on pin 1 which the sick Z7 has a voltage that looks like a capacitor charging. The differences in most of the resistances could just be due to the model's design. The 1.75 V on pin 1 of the healthy Z6iii is almost certainly below what would be required to operate the lens so some handshaking must take place once a lens is detected with the voltage then increased to a more reasonable value or applied to another contact to power the lens's micro-brain and focus, aperture, and VR actuators. It may simply be a logic signal.

    After a couple weeks, the behavior has changed on its own in a strange way. Everything listed above still works, but if both the battery and XQD card are installed, it may go into a mode where the memory access LED comes on for a second or so and repeats every 2 or 3 seconds. There is no way to really know what it's thinking and nothing appears on the memory card, but it does represent a battery drain, and if it actually writing something to the memory, reducing its lifespan. In that state, the battery does drain quickly even with no card installed and no flashing LED.

    Stay tuned.

    Spiratone Bello-DupliScope with Nikon-F Mount

    This contraption is basically a slide, negative, movie film frame, and other transparancy copying adapter with magnification adjustable from approximately 1:1 to 5:1 for an FX-format camera. It has a ring for magnification and a rack-and-pinion with bellows for focus. The only optic inside is a single lens with an effective f/number of 20 or 30. These turn up on eBay and elsewhere for next to nothing nowadays. Mine was $25+shipping. I probably paid too much but the seller was asking for much more. ;-) This sample is in very good condition cosmetic condition. Proably because like many such accessories, it was used once and put away. ;-)

    With its wide range of mangification, in addition to 35mm slides and negatives, it can handle 16mm, 8mm, and super-8mm movie film frames.

    The construction is nearly all metal except for the lens, bellows, a pair of Nylon guides, and the diffuser screen. Even the focus knobs are metal!

    After some cleaning of the lens and tightening of screws, it actually works remarkably well. With the high f/number lens, it should be done using manual shutter settings and relatively long exposure. But slides don't move around much. So this could be an alternative to an expensive closeup lens for copying slides or other mostly 2-D objects of similar size. There is no adjustable aperture so depth of focus is determined by the internal lens and the magnification. Manual focusing should be done using the bellows thing with the image in the LCD display (i.e., Live View) zoomed way up since there is no adjustable iris that can be stopped down.

    However, note that the minimum magnification is around 1:1 so a standard 35mm slide will almost fill an FX-format area at the camera. If used on an APS-C (DX) camera, only around 2/3rds (dimension-wise) of the slide will fit in the frame. The slide can be repositioned somewhat to capture a selected portion but never the entire thing.

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