The Industar-22 design was "borrowed" from Leitz Elmar. It was an improved version of a prewar collapsible FED lens (also known as Industar-10).
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The Industar-22 was a standard lens on the early Zorki cameras (Zorki, Zorki-C, early Zorki-2C) and was also a popular enlarger lens in the USSR in the 60's.
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Technical Characteristics:
Focal length: 50mm
Aperture: markings from 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: Coated
Finish: Polished chrome, Matte chrome
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: Coated
Finish: Polished chrome, Matte chrome
(source: fedka.com)
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