In article <1771212BB5S85.RWALTON@UNIVSCVM.CSD.SCAROLINA.EDU>, RWALTON@UNIVSCVM.CSD.SCAROLINA.EDU says...

>Got a question....I have an N90 and several auto-focus lenses...I
>also have access to a couple of Nikon/Nikkormat bodies and some nice, >non-AF lenses....To what degree are these interchangable?
>I tried putting an old Non-AF lens on the N90, and while it seemed to >fit it was a bit tight (b/c of the prong-thing atop the lens)....Any >advice?

Yes, DON'T put a non-AI lens on an AI body (except the FM, FE, F3,
or F4 - after lifting the AI tab on the body. Use stop-down metering
method [meter with the DOF button pushed]). Another poster had some errors in his compatibility list, so here goes, again (I recently
posted this): AI, AI'd, AIS, AF, AFD, E, and P lenses may all be used
on non-AI (with stop-down metering, if there is no chrome pin at f5.6
on the lens), AI, AIS, AF, AFD bodies. The only combinations to watch
out for are: non-AI lenses on AI (and similar) bodies that do not
allow moving the body AI tab out of the way before mounting a lens;
and non-retrofocus super wides (6mm f5.6, 7.5mm f5.6, 8mm f8, 10mm
f5.6, and 21mm f4) that require mirror lock-up before mounting on
the body, on bodies that have no provision for mirror lock-up.
So, to simplify: (uh, just read the first sentence again - it
basically covers it...). BTW, lenses (of any type) can be identified
as non-AI or AI by running your finger around the rear edge of the
aperture ring - if there are no ridges, the lens is non-AI; if there
are ridges, it is AI (and may be mounted on ANY Nikon SLR body ever
made).
Hope This Helps