04-16-2009, 10:37 PM
The part you have drawn the arrow too is an AI (auto indexing) follower that is attached to the black ring that
allows the f/stops to be read out in the viewfinder. It should be spring loaded and generally rests against the other black bit
that you see above it in the photo. When you turn the lens aperture ring it rides along.
It sound like the aperture ring which it is attached to is seized up - lube may be dried out.
Try working it back and forth to see if you can loosen it. Also on some Nikons (FM's and FE's) there
is a small button next to that nub that lets you flip it up so it is flat to the body. I never had an EM,
so I'm not sure if there is one or not.
The idea was to allow you to mix different generations of bodies and lenses - the AI's (auto indexing)
and non- AI. That adaptor also has a non-AI indexing tab on it (the silver tab with the "U" cut out)
It may be a case that this adaptor supposed to be mounted it the AI tab (the arrow) flipped up.
If that is the case it may be hard to get off. Look for a recessed pin on the face of the adaptor
that may be connected to the release.
allows the f/stops to be read out in the viewfinder. It should be spring loaded and generally rests against the other black bit
that you see above it in the photo. When you turn the lens aperture ring it rides along.
It sound like the aperture ring which it is attached to is seized up - lube may be dried out.
Try working it back and forth to see if you can loosen it. Also on some Nikons (FM's and FE's) there
is a small button next to that nub that lets you flip it up so it is flat to the body. I never had an EM,
so I'm not sure if there is one or not.
The idea was to allow you to mix different generations of bodies and lenses - the AI's (auto indexing)
and non- AI. That adaptor also has a non-AI indexing tab on it (the silver tab with the "U" cut out)
It may be a case that this adaptor supposed to be mounted it the AI tab (the arrow) flipped up.
If that is the case it may be hard to get off. Look for a recessed pin on the face of the adaptor
that may be connected to the release.