Volna-9 50mm f/2.8  Macro lens MC (M42 mount) + Canon adapter
The lens is interesting because of the very large stroke of the focusing ring, which rotates a full 360 degrees, focusing the lens from infinity to 24cm. When focusing, the “trunk” of the lens lengthens by about 3 cm, while the front lens does not rotate. The focus ring is metal. The front lens is deeply recessed into the lens frame, so this design serves as a kind of lens hood. Depth of field is indicated for aperture values F/4, 8, 16; there is a scale on the lens that shows the magnification level, from Macro 1:4 to 1:2.

Focal length: 50mm

Optical design: 6 elements in 5 groups

Aperture: F/2.8 to F/16

Number of aperture blades: 6 pieces

Front filter diameter: 52mm

Weight: 340g

MDF: 24 cm

Maximum magnification: 1:2

Manufacturer: Lytkarino Optical Glass Plant, Lytkarino