Lens Industar 26m ( I-26M) 2.8 /52mm M39 Fed USSR

Specifications:

 -Working segment: 28,8мм

 -Focal length: 52mm

 -Maximum aperture:2.8

 -Minimum aperture: 22

 -Number of lenses/groups: 4/3 Copy Tessar

 -Minimum focusing distance: 1 m

 -Resolution center/edge: 30/12 lines / mm

 -Number of diaphragm lobes: 10

 -Type of illumination: single layer

 -Mount: M39