Nikon D4 MBP and Remote issues

[JoshuaMB]

Hello,

I am trying to shoot some jewelry with a Copy Stand mounted Nikon D4 tethered to a Mac Book Pro. I first focus on the nearest point of the jewelry and set it as A, then focus to the rear most part and set B, then do the DOF and # of shots thing and hit Start Shooting.
The issues I'm having are that the A point seems to slip- i.e. If I set A, then set B, and then hit the large arrow to return to A, it will be off by about 5< . I can hit < 5 times and it will be about right, set A again, and then hit the large arrow to return to B, and it too will be off, readjust and reset B. Then once it's been adjusted and set, it seems I can go back and forth between A and B and they are set correctly- then start shooting and inevitably the stack will shoot past B and give me a few shots at the end that are well past B and unusable, and also, when it returns to A it is off again.
The copy stand is locked down, the camera is not slowly sliding down or anything... Using the 105VR so the focus shouldn't be falling down either.

tl;dr A and B points seem to slip "out of alignment" and not remain set.

[Stas Yatsenko]

That sounds like a problem with the lens skipping steps due to slack / slip in its mechanism. Try setting A and B points some distance apart, then move focus between them back and forth with the big < > buttons. If I'm right, you'll see the error accumulating, and the lens will always move slightly less distance than needed, so the points will become closer together.