My Nikon D90 started having an issue where the image in the viewfinder shakes, or taps whenever I turn it on or focus. Has anyone ever seen this issue? I'm assuming that it's the mirror.

I turned VR off and also tried it with another lens. I'm confident that it's the camera and not the lens.

I was able to catch it on video by putting my iPhone camera on the viewfinder here on YouTube.

  • I see in the comments you tried it with an 18-200. What was the other lens you tried? Have you tried cleaning the contacts in the body and on the lenses?
    – Blrfl
    Sep 30, 2012 at 0:01
  • I just want to share that I have the same issue on my Sigma 150-500 which I typically use on a D7000. I accidentally dropped that combination, and since that moment I have it. The lens is currently away for repair, at least I hope it is the lens :)
    – Fer
    Oct 2, 2012 at 18:56

4 Answers 4


Edit: The more I think about this, the less convinced I am that what I wrote originally is the answer, especially if this is happening with other lenses. I didn't see the same failure mode, either; mine just quit focusing. I'm going to query the OP about a couple of things in the comments and will revise this answer if I come up with anything else.

Original Answer:

Based on the OP's comment:

The first-generation 18-200 had problems with the AF hardware failing, so it might be that yours is on its way out. Mine died pretty early in its life and Nikon fixed it under warranty.

There were also a few cases where the front element fell out of the lens because the retainer ring wasn't properly secured, so you might want to check that, too.


That it's happening during focus may be a clue. I'm thinking that the metal part of the lens mount may have detached partially from the (plastic) body, and that the drive screw for the body's focus motor may be lifting the lower part of the lens (the angle would change twice per rotation). It doesn't take too much inadvertent tilt action to change the image. Try to gauge by feel whether a mounted lens seems to have any mechanical play at all (but don't use too much force; you don't want to make the repair more expensive than necessary).

  • I may have been mistaken in my initial post. I've retried the test with a different lens and can't reproduce it.. Maybe it's my lens (18-200 VR) and not the body.
    – user7801
    Sep 26, 2012 at 3:29
  • @user7801 -- if it's bad VR element behaviour, it's a little less disastrous. Though the 18-200 isn't cheap, it's probably a much easier-to-repair electrical fault; a lens mount problem could result in all kinds of alignment issues affecting all of your lenses (and it might even be more practical to write the body off, depending on the repair cost). But if it's happening on all of your AF-S lenses and not on AF "D" types, it'll be the mount.
    – user2719
    Sep 26, 2012 at 4:32
  • @StanRogers If I'm understanding your hypothesis right, wouldn't it only happen on AF/AF-D lenses, not AF-S? AF-S lenses' autofocus motors aren't anywhere near the lens mount.
    – Evan Krall
    Sep 26, 2012 at 23:32
  • @EvanKrall -- the screw would actually be fully-extended and engaged with the lens drive with an AF/AF "D" lens. With an AF-S lens, the drive should be driven back into the body under spring tension, and would (if it rotates) simply spin against the slightly-rounded tip as a bearing against the rear of the lens. If there is some slack in the lens mount's attachment, the lens will be somewhat angled by the spring's force, and the contact point will shift inward slightly when the drive is aligned with the lens diameter (and outward when it's perpendicular).
    – user2719
    Sep 27, 2012 at 8:02
  • @StanRogers: The spring behind the AF drive screw maintains pretty light tension. Given its position on the lower half of the lens mount, the sheer weight of an 18-200 would be more than enough to overcome the spring tension even if the mount were loose.
    – Blrfl
    Sep 29, 2012 at 23:48

I have seen this before - it was a VR fault in the lens. Can you attach the LENS to a different camera to confirm?

It cant be the camera mirror as that is either up or down due to the way it is driven - that and the image is moving the wrong way for it to be the mirror too.


This looks like the VR system is overcompensating. Can you reproduce this in Live View? If so, the lens is at fault; if not, the problem is in the body.

See also Why does Nikon D90 makes strange sound and shifts Mirror in Viewfinded Eyepiece after Shutter-release button is pressed

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