Carl Zeiss 50mm f1.8 Ultron

M42 mount

Albrecht W. Tronnier designed the Ultron 50mm f1.8 while working for Voigtländer AG, which filed the patent US3612663 for this lens design in 1969, and had it approved in 1971. After a short run, in 1972 the lens production ceased. Carl Zeiss (which owned Voigtländer) only made a few thousand lenses in Voigtländer plant, West Germany, which makes them quite rare.