Photographica Pages

An online guide to collectable cameras and related stuff


40/2 Zeiss Biotar for Contax (4-1/4cm or 4.25cm)


The less common 4-1/4cm Biotar with 4cm finder, and leather pouch for the finder.

The 40/2 Biotar was not-quite a wide angle, not-quite a normal lens of high speed, but mediocre performance. It was introduced in 1933 in black and nickel. The first batch had a nickel plated depth of field scale, and had no filter threads. The second batch in 1934 had the scale finished in black paint. The third batch was finished in chrome, with the inside aperture ring finished in chrome with black filled aperture numbers. This was in 1935. In 1936, the aperture ring was finished in black with white numbers, and the lens was finally given a 40.5mm filter thread.

In 1936 Zeiss changed the focal length to 4-1/2cm (or occasionally 4.25cm). The lens didn't change, just the labeling. Many lenses are labeled their approximent focal lengths. Prior to 1936, the 4cm lens fit well into a line-up with 28mm, 40mm and 50mm lenses. With the introduction of the 35/2.8 Biogon, it probably seemed prudent to center it's focal length as 4.25, more equidistant between th 35mm and 50mm lenses. All of these lenses were finished in chrome.

The lens was discontinued in 1938 production was less than 400 units marked 4cm, and 250 marked 4-1/4cm.

Finders to match the lenses were made in both black and nickel, and black and chrome finish, and could be found marked with either focal length.