Posted 06 January 2006 - 08:30 PM
"Can you tell me where you purchased your adapter and/or who manufactured it? I purchased a C-mount to Canon FD adapter with the intention of testing some Canon FD still lenses that I have. However, when I mount the lens to the adapter the aperture remains in the open position when I try to stop it down. Is this a defective adapter or am I just an idiot? I don't have any problems when using my C-mount to Nikon F adapter; it works splendidly. The Canon one, however, has my stymied."
I don't know who manufactured my adapter and it doesn't bear any identifying markings. If you watch Ebay for a while I'm sure one just like it will come up - just look for a ring on the adapter that says "open - close" or "C - O" or something like that. It really is a nice feature, as you can open the aperture to focus and then instantly stop down to your preselected aperture to shoot.
All of my FD's are the old breech-lock type with the chrome ring. On my lenses, I believe that the diaphragm actuation lever (the one with a kind of "dog leg" cut out of it) can be pressed in and will lock into place, making the aperture work manually, like a cine lens (this is according to memory, as I don't have a lens in front of me). Hope this helps.