Originally posted by UncleVanya Brian has done a lot of work for me already but I never thought to ask about this. Do you end up with manual aperture (I assume so). I would assume some lenses might have issues based on where the elements fall and how much room for mount surgery there is. That's great to know. Thank you.
With the Canon-FD 55mm f 1.2 conversion, I have same aperture setup as if it were a Pentax-D lens. Works perfectly with the green button. The lens Brian actually did for me was the Canon-FL 55 f 1.2, and that is the one that he also silvered for me. With the FL the lens aperture shuts down entirely by hand, and if you have enough light to focus with the lens in the shut-down state, you can actually use Av Mode; or you can focus, stop the lens down, and then shoot using AV mode. He also set it up such that you can manually focus with the lens wide open, and then manually stop down before taking the shot using AV mode.
This is not a particularly cheap procedure, and probably only worth doing on rather valuable lens. The Canon 55mm 1.2's, it seemed to me, fit into that category, so I spent $200-300 each on them to be able to use them with Pentax cameras. The Canon-FD 1.4 is another lens that I own and which has a fairly fabled status, and which some might consider to be worth converting. I do not know much about the 85mm, although I own one. It might be worth going back and reading the reviews or testing it yourself to see whether it offers something not otherwise available.
The easier way to do all of this, of course, is to get one of the Sony cameras and an adapter, allowing you to fit any Canon-FD or FL on the camera . . . but I shoot Pentax, and look forward to using these two lens on Pentax FF when it becomes available later this year.