How well does the adapter ring work on the more modern slr bodies? I have a bunch of manual focus 645 lenses that I'd like to use if it's worth doing. Ok. I'll come clean. I bought a Pentax istDL digital slr for the business and I'd like to save some company money by not having to buy a new set of lenses for this camera. That's what I want to use these lenses on. I still only use film for my artwork. B&H says this about the lens mounting of this body. "PENTAX KAF mount compatible with PENTAX KAF2, KAF and KA mount lenses Power zoom function not available K-mount lenses usable with restrictions S-mount lenses usable with adapter and restrictions 67/645 lenses usable with adapter and restrictions" What are the restrictions? I don't care if I have to use the camera manually just as long as it meters internally and runs the aperture blades when I shoot. Will the adapter ring allow me to get a ttl meter reading and run the blades? Any help will be greatly apreciated. If a moderator kills this thread because I used the "D" word, I'll understand.