Alf Beharie
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Upload & Sell: Off
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I finally received my second FD 85mm f1.2 L. Immediately after getting it out of the box I found that all the elements were there and in seemingly perfect condition but that the Iris was stuck wide open, so I stripped it down to investigate.
Turns out that someone has been fiddling with it before as several screws were missing and a large circlip inside was badly bent. After pulling out the circlip and removing the helicoid I discovered the problem was the Iris actuation ring/lever was about 180 degrees away from where it should be stopping it working the little Iris actuation cam...Someone had obviously been tinkering inside and did'nt know what they were doing. One of the helicoid stops was preventing me simply turning it to the correct position but as these were loose at this point I simply lifted out the offending stop turned the ring and replaced the stop. Now I could reassemble the lens using my converted aperture dial from the first lens to manually control the Iris. 
Now that I have been able to examine and measure a complete version of this lens I have been able to start working out exactly how to convert it to SA mount.
BTW, the fixed rear element is actually removable, not bonded in permanently as some may have thought. However, it is bonded into a very thin, fine-threaded ring which screws into the rear bezel. Luckily mine was'nt too tight so I could easily unscrew it and remove it for safekeeping whilst I work on the bezel.
Looks like I'm going to have to turn down the outer raised rim of the aperture dial retaining ring then I will have to turn the rear bezel in my lathe to produce a flat ring containing the fixed rear element retaining thread surrounded by a few mm of material to enable it to be fixed down. I will then turn up a new custom bezel from Aluminium and this ring will either be screwed or bonded, with expoxy, into place on the new bezel. Thats the plan anyway but the hardest bit will be finding an accurate way to hold the original bezel in the lathe without crushing it as its made of very thin Aluminium and therefore it is very easily deformed. Its not going to be easy thats for sure.
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