I want to buy into the contax/zeiss manual system. I already have a Yashica FX-3 Super 2000. I know that the contax/zeiss mm lenses will fit on my yashica camera, but will it otherwise harm the lenses? I'd rather buy the zeiss lenses first, to use on a later purchase of a contax body (I can't really do all at once). Thanks for your help.