Quote Originally Posted by Rol_Lei Nut View Post
There are some M42 lenses which won't mount properly on a Spotmatic F: as it is designed to allow full-aperture metering with the proper lenses, some lenses will catch on the aperture cam and won't screw in completely.
In my experience these are often German lenses (IIRC, some Zeiss Jena and Meyer samples).
It's likely that some M42 lenses of other brands designed for full-aperture metering might not work either (Fujica, Mamiya?).
I used a few CZJ lenses with my Spotmatic F with no issues and I never heard of one either.

Ian