Helios-44 Silver, 58mm F/2.0, 13 blades! M39- M42 mount, USSR Lens! Based on the lens Carl Zeiss Biotar 2/58. It has 13 blades diaphragm! Focal length: 58mm. Legendary Helios-44 with 13 aperture blades, lens with good sharpness and beautiful swirling bokeh.
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