Published in Autumn 2006 Zeiss Historica Journal
Author: Larry Gubas
See Pages 2 – 6.
While Carl Zeiss Jena did make a few of the Sonnar and Biogon lenses that were the patent based property of Zeiss Ikon in the Leica M39 screw mount, they were very few until the German military made such demands. In 1945, the Americans jumped on the same bandwagon for their Leicas and after July 1, 1945, The Russians ordered them as well for their Fed cameras (which was M39 but at a different screw pitch) and so they ended up on the German market to secure cash for the Russians and to some extent VEB Carl Zeiss Jena.
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