The FED 50mm collapsible lens design was "borrowed" from Leitz Elmar. This lens appeared first on the first FED in 1934 and was also known as Industar-10. In the late 1940's this design was handed over to KMZ and the Industar-22 was born.
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Question: The Industar 22 is a Tessar design and I'm told they were implemented to help standardisation of lenses after the war. Pre war Fed lenses have the diaphragm after the first element group and post war after the second so it sounds logical.
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The FED 50/3.5 design and appearance stayed virtually unchanged for decades, but the optical parameters were constantly improving. Restitution increased, coating appeared in 1949/1950. By the mid 1950's the lens was "finalized", and the later versions of the lens are sharp and contrasty, well suited for black and white and color photography.
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The FED is of the same quality as the Industar-22 and Industar-50, and it was made exclusively by the FED factory in Kharkov.
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Evoltution steps:
- first with a 1-turn focus (around 315 degrees)
- in 1935 it changed to a 1/2-turn focus
- new serial number system
- coated glass
- new aperature settings till 16 instead of 18, named 50mm instead of 50m/m
- 8 blades instead of 10
- new serial number system, serial number on the front side with focus markings
- lost button on the focus lever
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Technical Characteristics (1-turn version):
Aperture settings: 3.5 to 18
Optical Design: 4 elements in 3 groups
Glass: Uncoated
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Technical Characteristics (prewar 1/2-turn version):
Aperture settings: 3.5 to 18
Optical Design: 4 elements in 3 groups
Glass: Uncoated
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Technical Characteristics (postwar version):
Focal length: 52mm
Aperture settings: 3.5 to 16
Angle of Coverage (35mm film): 45°
Focusing: 1m - Infinity
Filter size: 36mm slip-on type
Optical Design: 4 elements in 3 groups, click to see drawing
Optical registration (back focus): 28.8± 0.02mm
Mount: M39x1mm, the lens mounts and RF couples with any Leica or Leica copy (FED, Zorki etc.)
Glass: since 1949/1950 Coated
Finish: Polished chrome, Matte chrome
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