This lens replaced its predecessor Industar-26m as a standard lens on the FED-3 and early FED-4 cameras. The optical design of the Industar-26m was improved and aperture stop-clicks were introduced.

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This is one of the newer multicoated M39 lenses made by the Soviet (now Ukrainian) photo industry. It is sharp and contarsty, with smooth focusing action and the aperture click-stops. The lens later evolved in all-black Industar-61LD.

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The lens was also made in universal 42mm mount for Zenit cameras, named Industar-61L/Z.

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Focal length: 53mm
Aperture: from 2.8 to 16, Click-stop settings
Field of coverage: 45°
Focusing: 1m - Infinity
Filter size: M40.5x0.5mm
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.)

The glass is coated; the barrel has chrome finish with black enamel rings.
(Source: fedka.com)

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Image #2: very early chrome I-61 (sovietcams.com)

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Known serial numbers:

#lens ______ #cam/type _____ mm _ blades ________________ owner/source

005530 ____ ? ______________ 52 _______________________ fotoua zebra type 1

061844 ____ lens only ________ 52 _ 10 ___________________ ebay

098473 ____ lens only ________ 52 _ 10 ___________________ ebay

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