Upload & Sell: On
What a package this is! As more FD L lens conversions appear, their image qualities can be judged in the digital age.
This project took a long time, as I also had to deal with the mirror issues. I believe the rear element of these type lenses need to be in the original spacings to achieve the designed image qualities, which in the case of the FD50L and FD85L, happens to be about 2mm out from the EF adapter toward the sensor. The 5D mirror swings up a little over 1mm from the EF adapter. There is no free ride. The mirror has to be shortened one way or another. I took off about 1.5-2.0mm from the leading edge of the 5D mirror. The edge of the mirror is rough as the silvered glass flecked away. Ugly but done. I put a longer 135mm focal length lens on the 5D and couldn't see the edge of the mirror, so at least I won't be reminded of the mirror grinding everytime I look through the viewfinder.
As I said, the rear element has a set position with respect to the film plane/sensor and I have determined this distance with respect to the distance back from the inside surface of the EOS adapters, I use. I have a jig that positions the rear element. Then, the lens is infinity adjusted, as a normal lens would be.
Most of the time, I convert a lens to EOS with the idea of streamlining the process for the purpose of offering the service. I'm not so sure about this and the FD50L. I actually have a working drawing at a local machinist for a 303 stainless EF flange that screws to the FD lens body with the original lens screws. The problem is the aperture control mechanism. When you pull out the FD mount, you pull out a part that makes the aperture work. That part needs to be re-created.
An even bigger problem is the 5D mirror issue. That is a deal breaker for all but the most extreme alternate lens user. The focusing screen makers cut their screens with a laser. Maybe they can offer cut down 5D mirrors with clean edges that can be installed by the user...
Coming from the crop camera world, I have to say I didn't know what I was missing. The apparent depth of field is much more shallow on a FF body and the bigger viewfinder is so much easier to manually focus. I have the Ee-S screen and a new "universal magnifying eyepiece" (2-13C). The AF-confirm chips I use are programmable for camera AF point, front or back focusing. Between all of the above, I can really get good focus results.
The FD85L has no field curvature that I can tell. I haven't noticed any of the usual aberrations, but I just started using the lens. Wide open flare or fringing is minimal. In the beginning, the 85mm focal length appealed to me more than the 50mm range, and that is still true, today. The camera lens combo is a lot of fun to shoot with and I guess if I had just one fast f/1.2 or f/1.4 lens in the bag, it would have to be an 85mm versus a shorter focal length.