Problem with canon fd lens on 35mm adapter
 

Good day there folks. I've got a little problem that just occured today and I think this is the right place to ask. I have a Jag35 adapter and until today I was using a Nikon 52mm 1,8 lens with no problems. Today I tried a Canon FD 50mm and noticed that although the focus ring works as expected, the F ring is not. Of course it turns normally but the iris won't open or close inside the lens. At the beginning I thought it's damaged but then I heard that you've got to attach it in a Canon camera that supports the lens in order to use it. This is a real problem. Is there any kind soul in this beautiful forum that knows a workaround that will allow me to use the F?

There is a pin on the back of FD lenses that needs to be fixed into position with a bit of wire or broken off toothpick to enable manual aperture.

Does the FD lens automatically default to wide open if you leave the pin alone?

Sorry for not replying, but I was getting married! Well, shame on me, the lens were going wide open when I was attaching them to the adaptor but were closing when I was taking it out. I could see that the image was OK when on, but I couldn't change the exposure. Still can't, but I don't mind now, since it's OK to have it all way open and change it through the camera iris wheel.

Thanks for your replies guys! :)

Yeah I probably should've updated that. I have two lenses, an older 35 with silver ring, and a newer 50 with the black ring. Didn't really care about adjusting stops just wanted both lenses wide open. The 35 was already wide open, but the 50 I had to use the two screwdrivers, turn the inside ring till it 'locked', adjust to f1.4, then unlock it and it stayed open when putting it on the mount - all good!

DOF at full open is pretty, but you're using the full diameter of the lens entrance so you'll get a very soft image and aberration. You will find you get a much nicer picture if you stop down; my magic number is f2.8.