Soviet lens Helios 44 siver 2/58 M39/M42+ adapter Sony E NEX. Focal length 58mm. There is an erroneous opinion that the first Helios-44 were assembled from the components of the "biotar". There are simply no parts and finished glasses left for Biotar, therefore the optical design has been recalculated for our grades of glass with minor changes in technical characteristics.
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