Contax/Yashica lenses

The Yashica / Contax lens mount was introduced in 1975 simultaneously on the Contax RTS and on the Yashica FX-1. From the beginning there was a Yashica range of lenses, called the Yashica ML, and a Zeiss range, which displayed the T* multi-coating. Some Zeiss lenses were made in Germany and the rest in Japan under Zeiss license.

The mount was modified in 1985 with the new Contax MM lenses permitting to use the program and shutter-priority modes of the Contax 159MM and subsequent bodies. The new MM lenses are distinguished visually by the color of the f-stop markers: the highest f-stop on the MM lenses is marked in green. On the older lenses, also called AE lenses, it is marked in white. The lenses are physically compatible but with the older lenses you cannot use the exposure meter of the newer bodies to its full potential.

The program mode of the late manual focus Yashica bodies (FX-103, 107 / 108 / 109 MP) works differently and functions with any Yashica / Contax lens, older or newer. There was no Yashica lens with MM full compatibility.

The unique Contax AX camera allows autofocus using these lenses, by actually moving the film plane (rather than the lens) back and forth. The AX can actually be used with other lens mounts via adapters.

Later Contax SLR lenses for the auto-focus Contax N series use a different mount, aptly called "N mount."