On Tue, 10 Jul 2012 21:01:30 -0700, nospam wrote:

the d50 has a focus motor. the others do not.

you can tell by a mechanical coupling pin around the 7 o'clock position
when looking into the mirror box, or by just trying a non-afs lens.

Ah, I see.
a) My Nikon D5000 & D60 do not have the mechanical coupling pin
b) But, I can clearly see the coupling hole for my D50

Here is a shot, taken by the D5000, of the D50 and D60 side by side:
http://www3.picturepush.com/photo/a/...40/8705051.jpg

Thanks for that. I will continue reading on!