Smena Stereo (1972-1977)

PK3605.  35mm 24x72mm (24x36mm) STEREO, plastic prototype camera, released in 1972-1975. Axial Galilean viewfinder. Lever cocking, crank rewind. Central shutters coupled to cocking and shutter release mechanisms. Speeds: 1/15s + 1/250s + B, engraved on the left (sometimes on the right) shutter. 4/40mm Triplet-43 lenses, with marked hyperfocal distance (3m). Diaphragm: 4 - 16. Few types of the shutter release knob and different markings on body are known to exist. Horizontal-style body coverings. Never series produced. 

PK3605 - Smena Stereo prototype camera from LOMO archives

PK3610.  35mm 24x72mm (24x36mm) STEREO, plastic prototype camera, released in 1975-1977. Axial Galilean viewfinder. Lever cocking, crank rewind. Central shutters coupled to cocking and shutter release mechanisms. Speeds: 1/15s + 1/250s + B, engraved on the left shutter. 2.8/40mm Industar-73 lenses, with marked hyperfocal distance (3m). Diaphragm: 2.8 - 22.  Horizontal-style body coverings. An only real sample is known to exist in collections.

PK3610 - Smena Stereo prototype camera

Smena Stereo Automat (1972)

PK3615.  35mm 24x72mm (24x36mm) STEREO, plastic prototype semi-auto camera. Axial Galilean viewfinder. Lever cocking, crank rewind. Central shutters coupled to cocking and shutter release mechanisms. Speeds: 1/15s + 1/250s + B. 4/40mm Triplet-43 lenses, with marked hyperfocal distance (3m). Diaphragm: 4 - 16. Vertical-style(!) body coverings. Never happened to see this sample alive.

PK3615 - Smena Stereo-A prototype camera from LOMO archives