The Carl Zeiss Ultron 50mm f/1.8 is standard prime lens for 35mm SLR cameras.
It came in two mounts: M42 and Icarex BM Some sources say that it was the sharpes standard prime lens of the late sixties and early seventies. Its front lens is konkarv and thus rather unusual. This lens was the precursor of the Voigtländer Color Ultron 50mm f/1.8, but with different optical design. The Zeiss Ultron has no filter thread, but a bayonet mount for filters.
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Posted by: Andreas Lindemann Date of publication: 13.08.2019