So that explains why some detail pics shown here of aperture rings look different-they are made of metal.I suspected so!
While my FDL version is reasonably precise,it did have an odd feel due to the 'square' shaped end-on-roller-bearing they use (similar to most FD lenses).I replaced it with a normal spherical ball bearing and lengthened the spring to compensate.It still has the characteristic 'bicycle with folded newspaper in spokes' sound but feels much smoother.
I'll be selling mine sometime in the near future.When i do i'll make sure i post a notice here so true enthusiasts get first chance at it
Just wanted to post an update...I spent several hours on my lathe yesterday reducing a big lump of ally down to a precision made "top hat" shaped ring. This ring screws onto the lens using the four aperture dial retaining ring screws.
I parted off a ring containing the fixed rear element retaining thread from the original Canon "top hat" ring and this fits perfectly into the top of the new ring.
The SA mounting plate is a perfect fit over the new top hat and will be secured using the four original securing holes via four tapped holes in the new plate.
I turned the aperture dial retaining ring to reduce the thickness but after checking last night it will still need another couple of mm removed.
Hopefully it wont take too long to get it up and running now.
I finally sold my FD 85 L yesterday. I got only 360 EUR for it, an unbelievable bargain for a lucky Italian fellow.
I made no minus in cash, but considering the effort I had with the conversion, I am a little disappointed.
Well, now I am very sure that I will keep my FD 85 SSC Aspherical forever!
The latest news is I have now successfully converted my FD 85mm f1.2 L to Sigma SA mount :
Now here is the strange part...I made full provision to include the fixed rear element in the conversion process but I may not bother using it now as as it does'nt seem essential because the lens seems to work OK without the fixed rear element in place. As such it focusses to infinity no problem, in fact, it can actually focus past infinity, so I may need to add a shim or two now between the lens and the SA mounting plate.
Here are the components I needed to convert it:
And heres how they fit on the lens (note: I sprayed the internals of the "top hat" matt black before making up this photo) :
Fantastic work! I always envy anyone with a lathe at one's disposal
The point of including the fixed rear element is very obvious on the original lens once you take some shots and examine the images with/without the elment in place. Unless you are into dreamy hazy images, you will have to close down seriously to make this FAST lens usable . This is similar to some other lens with fixed rear element, e.g., FD 55/1.2 Asp, FD 50/1.2L.
But since your second-last element is not original, the optics is altered. So who can say for sure? Good luck in this adventure!
Fantastic work! I always envy anyone with a lathe at one's disposal
The point of including the fixed rear element is very obvious on the original lens once you take some shots and examine the images with/without the elment in place. Unless you are into dreamy hazy images, you will have to close down seriously to make this FAST lens usable . This is similar to some other lens with fixed rear element, e.g., FD 55/1.2 Asp, FD 50/1.2L.
But since your second-last element is not original, the optics is altered. So who can say for sure? Good luck in this adventure!...Show more →
This is the second FD 85mm f1.2 L i've bought...Unlike the first one, which had both rear elements missing this one has mint optics but its been tampered with inside as the circlip between the the two halves of the helicoid was badly damaged and the aperture actuation lever was 180 degrees from where it should be so it was'nt stopping down when I first received it. I got it to stop down ok but the circlip was beyond recovery...Does'nt seem to effect the workings of the lens with it removed though so I'm not too worried.
Interesting what you say about the dreamy hazy images without the fixed rear element in place...I have'nt actually taken any sample pics with it yet as I only finished it late last night and had to go to bed early for work today so I will have to take a few samples to confirm that...It looked very sharp through the viewfinder last night though, even wide open.
OK i took a few samples and you were quite correct...dreamy and hazy. I fitted the rear element on and tried again and its wonderfull.
Only problem is I cant focus to infinity with the fixed element in place so it will need more work to get it spot on.
: 
. This is similar to some other lens with fixed rear element, e.g., FD 55/1.2 Asp, FD 50/1.2L.