Originally posted by JCSullivan This is quite interesting BUT, why would anyone want to muck-around with this?
Why or how would the AF get screwed - excuse the pun.
The camera may not have been set correctly at the factory as these are very, very finite adjustments and therefore need to be adjusted very critically. The amount these screws need to be adjusted is so small, you can therefore see that it doesn't take much to have them incorrectly set in the firat place.
In my opinion, I believe that the cameras should allow for this sort of adjustment easily. The new K20D will have individual focus adjustments for up to 20 AF Pentax lenses in the menu so that when you put the lens on the camera, the camera will recognise that lens and then adjust the focus to suit that lens. In other words, you will test each of your Pentax AF lenses and see if each lens FF's or BF's and then adjust each particular lens so that it focuses correctly via a menu on the camera. This will be stored in the memory so that each time you put that lens on the camera it recognises it and focuses according to the pre set focus that you set for it.
The FF Canon 1DS MKII etc have this same feature in their cameras as their lenses also have this problem.
The Nikon D70(and more than likely other subsequent models) has focus adjust screws in the mirror box.