The Contax 21mm f/2.8 Carl Zeiss T* Biogon is an ultra-wide prime built for the Contax G rangefinder system, pairing the Biogon optical layout with Zeiss T* multi-coating. Introduced in the 1990s as part of the autofocus G-series line-up, it was designed to deliver rectilinear wide-angle coverage in a compact body suited to reportage and landscape work on 35mm film.

At recent UK auction the 21mm f/2.8 Biogon has shown a wide spread: hammer results in our records run from £210 in November 2025 up to £480 from an earlier 2011 sale, with a two-sale median of £345. As of 2026 the more recent hammer price is the better guide to what a clean copy sells for today at saleroom level, while exceptional examples with the matching 21mm viewfinder and original box can push the value higher. Buyers should remember these are wholesale hammer figures; retail and dealer asking prices typically sit above this band.