I have a Ef mount Ursa camera and I wanted to buy a Zeiss set of primes that would emulate the look of the CP.2. From my readings, the CP.2 have the same optics as the Zeiss contax but with different housing. I know the ZEs are different, but what about the ZFs? Are the Contax and the ZFs the same optically? I was inclined to buying the ZFs as I have a bunch of EF to Nikon adaptors.