Using an F100 with older manual focus Nikkor lenses

Discussion in 'Nikon' started by chris_klug|3, Sep 10, 2011.

  1. I recently purchased a used F100 along with an older manual focus Nikkor lens. Reading the manual, it says that Aperture priority
    metering should work. But regardless of what f-stop I set the lens, it picks a shutter speed as if the lens is wide open, so if I set the
    aperture at, say, f/5.6, the frame will be severely underexposed.

    What am I doing wrong?

    If I manually set the shutter and aperture, the frames are properly exposed.

    Chris
     
  2. Are they AI/AIS lenses? It needs the AI aperture coupler to meter...
     
  3. Is that lens a pre AI model. see here
    http://www.mir.com.my/rb/photography/companies/nikon/htmls/models/specroom98/f100/f100spec.htm
    On this page you can check the serial number.
    http://www.photosynthesis.co.nz/nikon/lenses.html
     
  4. The F100 can't mount pre-AI lenses unless they've been converted, so I doubt that's Chris' problem.
    Chris, are you setting the aperture using the lens' aperture ring or the camera body's controls?
     
  5. Craig, that's not quite true, some of the early-mid 60's non AI lenses have a thin enough aperture ring that it slides under an AI tab on a camera, or may not extend far enough over the lens mount to even contact the AI tab. Most annoying when you want to convert one to AI, you have to add material, not just machine it off with a mill.
     
  6. True, but that's a pretty small minority of pre-AI models, as I recall. More likely he's got an AI or AI-S lens.
    Just to be certain, though: Chris, what lens are you using?
     
  7. If it's AI or AIi converted and still doesn't work right, you might check for oily or sticking aperture blades.
     
  8. Manual setting gives proper exposures, so I doubt the problem is sticky aperture blades.
     
  9. The F100 can't mount pre-AI lenses unless they've been converted
    Not quite explicitly true. The problem is that the F100 can mount unconverted pre-AI lenses. You can, but you shouldn't. Most are indeed incompatible and are unsafe to mount, and if you happen to forcefully mount the wrong pre-AI lens enough times, damage will occur to the AI meter coupling tab.
    When a manual focus (non-CPU) lens is mounted on the F100, it automatically defaults to aperture control via the aperture ring in A mode, and rotating the command dials has no effect, so I can't see that being the problem.
    Sticky aperture blades would cause over-exposure, not the severe under-exposure that Chris is experiencing, so that's not it.
    Chris - if the lens you are using does not have two rows of numbers on the aperture ring, you may be using a pre-AI lens that has not been AI converted. If so, stop using it until you can confirm that it is safe to mount.
    If the aperture ring does have two rows of numbers, it is an AI/AiS lens and should work correctly in A mode. When you say "I manually set the shutter and aperture, the frames are properly exposed" does it also meter correctly in M mode when you change the aperture? If not, check the small plastic tab at the 1 o'clock position on the F100 lens mount for damage. If it does meter correctly in M mode, then it's a real mystery to me how it could work correctly in M mode but not in A mode.
    00ZJf7-397579584.JPG
     
  10. First off, thanks for the quick replies. I am a long-time Canon shooter who has always been encouraged by friends to try Nikon. Hence the purchase of the F100. I love the ergonomics, so I really want to get this to work. I am at ease with focusing manually, but the metering with this body confuses me at this point.
    Answers: Yes, I am setting the aperture ring to control the f/astop. The display reads "- -" for the aperture, as the manual says it will.
    Manual setting of f-stop and shutter work, so I doubt it is the lens blades.
    The lens serial number is 2710362, which that web site lists as a Series E New, made from 1981-1985.
    The lens was given to me free, so that's what I had to test with. I love primes, so it seemed ideal.
    Thanks so much for the help.
     
  11. Michael said:
    "If the aperture ring does have two rows of numbers, it is an AI/AiS lens and should work correctly in A mode."
    It does have two rows of numbers.
    When you say "I manually set the shutter and aperture, the frames are properly exposed" does it also meter correctly in M mode when you change the aperture?
    Hmm, let me go outside and check that just to be sure. I'll come back and report what I find.
    Chris
     
  12. All Series E lenses are AiS and are 100% compatible with the F100, so that can't be the problem.
    Chris - with the lens mounted on the body, look closely at the small tab highlighted in the above photo while you rotate the aperture ring. This tab should "follow" the aperture ring as it is rotated. If it doesn't, there's a problem with the AI indexing mechanism. If it does, well I'm completely stumped as to the source of your problem.
     
  13. ShunCheung

    ShunCheung Administrator

    The lens serial number is 2710362, which that web site lists as a Series E New, made from 1981-1985.​
    Series E lenses are AI-S lenses. To be on the safe side, if you could, please post an image of that lens. It is ok to use your Canon DSLR to capture that image. :)
    To check the aperture stop-down mechanism, I would suggest mount your lens on the F100 and set the aperture to f11. Press on the depth-of-field preview button on the F100 and see whether the viewfinder gets drak or not. If it doesn't, you can check both the body and lens to see whether the mechanism is working. We'll get into the details if necessary.
     
  14. Ok, did some experimenting and took some pictures (with my iPhone, btw).
    The first test I did of the camera (of any new camera I work with) was to test the camera using my Sekonic meter. Those are the test images I referred to when I said "it works manually." Use the meter, read 1/125th @ f/5.6, fire, boom. This is potentially an important detail.
    Ok, so setting the camera to 'M' and looking into the viewfinder, I noticed a detail I had missed before. When I adjust the aperture up or down, the 'exposure scale' along the bottom of the window (where it shows you whether you are over or under exposing the frame never moves. If I adjust the shutter speed, it adjusts appropriately. Not so much with the aperture on the lens.
    Chris
    00ZJk0-397661684.jpg
     
  15. Shun said:
    "To check the aperture stop-down mechanism, I would suggest mount your lens on the F100 and set the aperture to f11. Press on the depth-of-field preview button on the F100 and see whether the viewfinder gets drak or not. If it doesn't, you can check both the body and lens to see whether the mechanism is working. We'll get into the details if necessary."
    Ok, performed that test, and yes, the viewfinder dims.
    Chris
    00ZJkB-397667684.jpg
     
  16. Michael said:
    "Chris - with the lens mounted on the body, look closely at the small tab highlighted in the above photo while you rotate the aperture ring. This tab should "follow" the aperture ring as it is rotated. If it doesn't, there's a problem with the AI indexing mechanism. If it does, well I'm completely stumped as to the source of your problem."
    I've seen that tab on other lenses, but this lens has no such tab.
    Chris
     
  17. The indexing tab is on the BODY. There is a corresponding AI "ridge" on the lens, and this is present in the photo of your lens that you posted above. Please mount the lens and take a close-up photo similar to the one below. Since the camera metering does not respond in M mode, I suspect the AI tab on your F100 has been damaged/broken.
    00ZJkJ-397671684.jpg
     
  18. Chris,
    did test with my F100, that had been in the storage for only less that six months.
    Put the lens on, set the camera on A. Turn the aperture ring on the lens. The exposure time on cameras' top panel or viewfinder should change accordingly. If this is ok, then the (AiS) linkage works.
    If you already tested that the DOF preview is working, then the operation chain from the camera to the aperture in the lens is working. As indicated by working M setting too.
    Hopefully it is nor camera internal issue, as I may remember that a mechanism measures the exposure just before the shutter opening. So if it is that, then the behaviour could be what you described. M works A not.
    Check also with another lens and new batteries.
    -- Kari
     
  19. Michael
    Okay, I will mount the lens and look as you describe. Attached is a picture I took of that area today. I see no tab as you describe.
    Chris
    00ZJl9-397697684.jpg
     
  20. Your tab is broken off. Maybe a previous owner broke it with a non-AI lens?
    On mine, the tab is a bit above the white dot, where yours has what looks like a jagged edge...
     
  21. Chris - don't bother mounting the lens to take a photo.
    Your F100 is broken. Return it to the seller for a full refund, including your shipping costs if you purchased it on-line. Apparently a previous user has mounted a pre-AI lens which jammed on the AI tab and broke it off. With no tab, the camera will only meter and expose properly when a lens is used wide open. At all other apertures it will under expose. In other words, this one requires a repair whose cost will may equal or exceed the price you paid for the camera.
    Sorry that your first experience with this truly fine and capable Nikon (I use to own one) is from a seller that sold you damaged goods.
    Good luck with the return.
     
  22. ShunCheung

    ShunCheung Administrator

    Sorry Chris, as Andy and Michael point out, your F100 is damaged. In particular, the aperture follower tab is damaged.
    00ZJlf-397701584.jpg
     
  23. On second thought, I feel like I should speak up for the F100 :) That piece isn't fragile or anything - not as solid as the metal one on an older camera, but it won't break in normal use. Somebody's been clumsy with it, maybe pushed too hard trying to mount an incompatible lens or something. You should get a refund and look for another one, because it's normally an excellent camera.
     
  24. This is terrible. Taking it back is not possible. I'm stuck with it. This is due to my ignorance about Nikon bodies. It SEEMED to work when I examined it. My only option is to have it fixed or junk it, I guess. Just curious, would modern lenses need the tab to meter correctly?
     
  25. Unfortunately modern lenses (i.e. CPU enabled lenses) also require the AI tab. It is used to confirm that the aperture ring is set to the correct minimum aperture position in P, S, A and M modes when aperture control is set to the command dial. Without the AI tab to determine the position of the aperture ring, you will get a 'fEE' error in all exposure modes, and the camera will lock up and refuse to fire.
    The only way you can use it as it is now with an autofocus lens is to set custom function 22 to (1) so that aperture control for CPU lenses is via the aperture ring (see page 75 of the manual) and use it in M mode only. P and S modes will not function, as they require aperture control via the command dial, and with the broken tab a 'fEE' error will occur. A mode will give you the same underexposure error as you are getting with the manual Series E lens.
    Hope that made sense. If not, message me privately and I'll try to explain it better.
     
  26. G lenses don't use the AI tab. That's lenses that don't have an aperture ring - these will work as normal on your camera.
    If you can find somebody to do the repair I don't think it should be too expensive. If they can get the part, it's a simple one, so you'd be looking at the minimum time they'll bill plus a few dollars for the part.
     
  27. Right you are Andy L. 'G' lenses, and only G lenses, can meter without the AI tab. Wasn't thinking it all the way through there obviously. But any lens fitted with an aperture ring is going to be severely restricted.
    It is worthwhile getting a repair estimate. The cost will mostly be the labour involved, as the replacement assembly is a simple piece of plastic with a spring (p/n 1B610-059)
    00ZJoA-397733584.jpg
     
  28. Nikon calls it a "coupling unit" in the parts list for the F100 ...
    00ZJoF-397735584.jpg
     
  29. You guys have been wonderfully helpful. I will get this fixed. I had heard great things about the photo.net community,
    and you guys delivered.

    Thank you.

    Chris
     
  30. I looked at my F6 and FM2n and I see no AI indexing tab. I know they work with AIS lenses as I have used them on them. They are the ones with the orange high F stop numbers in two rows. I don't own any AI lenses unless the Nikon mirror lenses are considered that.
    DaveO
     
  31. Never mind my last post. I must be half blind. I see the indexing tab now on these cameras. It is not as large or pronounced as I was expecting. I put an AIS lens on them and they hit the tab and rotate it.
    DaveO
     
  32. I looked at the tab on Chris's F 100 in the picture and it doesn't look shorter than mine or broken. Perhaps, that is not the problem.
    DaveO
     
  33. Look again. Closer. ;) :)
    The tab should be visible on the outer circumference of the indexing ring at 1 o'clock. See Shun's photo posted Sep 11, 2011; 06:35 p.m. Now compare that to Chris's photo posted Sep 11, 2011; 06:10 p.m. It's clearly missing and not there. Broken off. End of story. Mystery (and problem) solved.
     
  34. ShunCheung

    ShunCheung Administrator

    I hope this image helps. I bounced the flash from the left side so that hopefully the follower tab stands out more.
    00ZLPs-399165584.jpg
     
  35. Thanks so much again. Yes, sad to say, the tab is missing on my F100.
    It has already arrived at KEH for repair. The estimate was $120. They are examining the camera now and I await a call confirming the diagnosis.
    Chris
     

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