Contax G is an autofocus camera mount produced by Kyocera during the 1990s. There are only two cameras in the system, the G1 and G2. These cameras are premium in every sense of the word, from build quality to lens lineup to features and more.
The G’s autofocus can be described as a ”hybrid rangefinder” system. While there is no rangefinder patch like you’d find in a Leica M, the Contax uses IR beams fired from two windows to triangulate focus distance passively. This is the same principle as manual rangefinders, but in AF form.
Unfortunately, this passive AF system drew ire from some photographers for inaccuracy. While a lot of this isn’t the fault of the camera, the G2 introduced an active AF system on top of the passive rangefinder system. The passive system achieves general focus and the active system fine-tunes it, leading to many more in-focus shots that can take advantage of the lenses.
One of the defining features of the G system are the lenses. There are seven of them, all made by Carl Zeiss to the highest standards in the world. These lenses are widely regarded as some of the best lenses ever made, for film or digital. From the ultra-wide 16mm Hologon to the world’s only zoom lens for rangefinder cameras, there are many interesting options in the G mount.
Because these are electronically-controlled rangefinder lenses, they are not particularly easy to adapt. It’s only possible to adapt them to certain mirrorless systems and other rangefinder systems, like Leica M. You will need an adapter with its own focusing helicoid, since the Contax lenses do not have one.