Zeiss ContaxForum for the classic Zeiss Contax I, II, III, IIa, IIIa , G series, and if you want to push it, the nice Contax point and shoots. Some spill over from the Kievs, the Soviet copy of the Contax II/III can also be expected. Plus the ONLY production camera ever made in classic Zeiss Contax Rangefinder mount WITH TTL metering ... the Voigtlander Bessa R2C.
Most lenses are TTL for exposure. The 16mm is not. A P or a UV filter is good. I would suggest Contax, Heliopan or B+W. Rember, the least quality of glass, will be the quality of your photo.