I have an AE-1 Program and recently purchased a Canon 50mm f/1.4 FDn on Ebay, however when I received the lens it doesn't seem to be snapping and locking into place when I fully twist it onto my camera (which works for all of my other FD lenses). The lens rotates to its full mounted position, yet the lens' mount release button will not come out to lock the lens in place so I'm able to rotate it back off the camera. I made a short video demonstrating the problem, and comparing it to my 28mm lens which properly locks (this was for the seller), and a second video to show the back side.
Video of the problem (50mm compared with 28mm):
Second video of the back of the lens (50mm):
Pictures here: 50mm 1.4 lens mount won't connect
I can't find any solutions for this anywhere and every part of the lens looks to be in proper shape to my eyes, except that the silver button doesn't pop out and lock when mounted. Any idea what the problem could be or how this could be remedied? Any help would be much appreciated!
