Hi, I'm hoping someone may be able to help. I recently bought a Canon A1 with a 50mm FD f /1.8 S.C lens. Canon FD 50mm F/1.8 (II) There is no green A for automatic on my lens. It only has the aperture numbers and a green circle at the end. Does anyone know if the green circle performs the same function as the A on the newer/more common FD lenses? I am quite new to all this so please be kind Thanks