Reviving a pretty old thread, but there are two reasons: First, the original post was truncated a while back (when the forum migrated to a new server, IIRC), so I'll repost the more important bits. Second, there's an update to the subject which may be interesting to someone, so... here goes .
I'll describe the precedure all the way, and there's a link to the pics near the end.
First off, the Canon FD to Nikon F adaptation was just a direct mount swap: Just remove the original mount (including some coupling levers and such) and install the new mount. This was a solid piece of metal, with a Nikon F baionet on one side and a slanted colar on the other (maibe a telescope or bellows adapter?). Shaved the colar and a little more to get about the correct thickness for infinity focus and that was it.
Then, I had to couple the aperture ring to the aperture mechanism. There is a lever in the original mount that connects to the iris mechanism, and is moved by a tab in the aperture ring as it rotates, hence setting the aperture. This lever was removed with the mount, so I added a highly sofisticated device to restore the connection (as you can see in the first two pics, the "sofisticated device" is a bent paper clip ). Notice the ring where the new part enters the mechanism, and let's call it Nr. 1 (more on that later).
Finally, the original adaptation was completed with the auto aperture. There is a ring (let's call it Nr. 2) in the iris assembly that turns to open and close the iris. How much the iris closes is limited by the position of the Nr. 1 ring (which is set by the aperture ring outside).
So, connect this ring to the lever in the camera that operates the aperture and you get auto-aperture. The problem is that ring Nr. 2 turns counter-clockwise to close the iris, contrary to what is supposed to happen on Nikon .
So, I needed two new parts: first (pics 4 and 5), a tab in ring Nr. 2 (it is simply glued, not the best, but the ring is part of a roller bearing - if you don't know what NIGHTMARE it is to reassemble one of these, DON'T TRY IT! ). The second part (pic 3) is a pivoting lever: one end pushes the other tab (it has a spring to make it return), and the other connects to the camera´s aperture actuating mechanism.
And that was basically it. Pics 6 and 7 show the lens as it was then (notice the aperture ring, with the f-stop markings reversed to what is expected for Nikon.
Many years later (which included some time adapted to Pentax K ), I've returned it to Nikon mount, but this time went "all the way" and added an aperture reading pin, bringing the lens to AI-spec (pics 8 and 9). However, in this case it was not just a case of adding the pin, as the mechanism inside is reversed. The key is ring Nr. 1. It has several diferently sloped areas, which control the position of ring Nr. 2 (via the triangular part in pic 4). These areas are diferent and adequate for diferent systems (in the original position, the iris closes when ring Nr. 1 turns CCW, so it was a question of disengaging the "paper clip part" and turning the ring freely until engaging a reverse section. Now, turning the aperture ring clockwise (and hence ring Nr. 1), closes the iris (as is supposed to happen on Nikon lenses ). AND, with this the paper strip in the pics DOES indicate the correct f-stops .
Notice: I guess this is a nice tip for all us tinkeres: I've seen this sort of thing on several 3rd party lenses, so it MAY be possible to do this on other interesting lenses with not-so-interesting mounts (May be trying this on my Cosina-made 19 mm Vivitar...).
Oh, by the way: What I've used for the parts (appart from the paper clip), were pieces of windshield wiper springs (the long strips of stainless steel inside the rubber wipers). Burned them to remove the springyness (allowing me to bend it as needed) and that was it ...
Anyway, here's the link for the pics:
https://nis.nikonimagespace.com/html/gu … 5Qttg-n5uw
Hope you enjoy, coments are welcome. I'll try to post some more samples soon.
EDIT: Done, check here:
http://forum.manualfocus.org//viewtopic … 89#p153589
Last edited by glimavitor (2016-08-14 09:18:10)
Nikon: D7000; F2; F4; FA. RMC Tokina 17/3,5; Ensinor 24/2,8 Macro; Nikkor: S.C. 50/1,4; AI-s 28/2,8; Micro 55/2,8; 80-200/4; S. E: 35/2,5; 100/2,8; Viv. S. 1 105/2,5 Macro (Kiron); MC Rokkor PG 58/1,2; Canon FD 300/4; Pentacon 135/2,8.
Pentax: K20D; CZJ Flek 20/4; SMC Pentax: A 28/2,8; 50/1,7; M 50/1,4; Tak. 50/1,4; Tamron Adall 2: SP 90/2,5 Macro; SP 60-300; 35-70/3,5 CF; .
And some others...