RF-3
lens for duplicating camera RUZ-50, 780409
300 mm, 1:10, M52
LOMO, Leningrad, USSR

Perfect condition. Lens is clear and clean, without any fungus or scratches. Inside the lens there is some microdust. Body has small signs of age. Aperture works properly and tightly. Aperture ring has a small backlash. Aperture blades have a bit oil.

This is a large format lens for duplicating camera RUZ-50 It's one of the best USSR lenses for large format cameras.
Camera RUZ-50 was used in polygraphic industry. Its frame size was 18x24 cm and lens RF-3 was default for it.
Lens RF-4 replaced Industar-11 having much better resolving power.

This lens does not have focusing ring. Focusing is achieved with moving of the camera body. Thanks to the lens sharpness enlarger was used to reproduce books, newspapers, drafts, manuscripts and so on.

This lens is interesting with a cut at the body. Additional diaphragm of necessary shape (square, rectangular, hexagonal and so on) can be inserted through that cut.

Lens has one-layered anti-reflection coating.

haracteristics: 
Lens s/number - 780409
Number of lenses - 6 in four groups
Frame size - 18x24cm
Number of aperture blades - 12
Angle of view - 43o
Limit of aperturing - 1:10 (max), 1:64 (min)
Type of mount - M52x0.75
Resolving power - (centre/edge) 35/18 lines/mm
Dimensions (mm): 65*65*60
Mass - 264 g