Zenit-S is a 35mm film SLR camera made by KMZ and produced between 1955-61 with quantity 232.949 units. Zenit (Cyrillic italics Зенит-C = Зенит-C), means Zenith, a point in the sky that appears directly above the observer. The Zenit S is a further developement of the original Zenit camera, having a sync contact added for flash. The C stands for S which is Synchronized for flash. It belongs to the long lasting Zenit series.
This model has 6 types and 3 sub-types. 
- Embossing on the front of prism: KMZ logo
- Lens: Industar-22 (ИНДУСТАР) 50mm f/3.5
- Other standard lens is Industar-50 50mm f/3.5
- Mount:KMZ's ZM39 screw mount.
- Lens release: simply screw counter clocwise
- Aperture: f/3.5-f/16; setting: ring and scale on the lens
- Focus range: 1-20m +inf
- Focusing: ground-glass screen, ring and scale w/DOF scale on the lens
- Shutter: rubberized silk double cloth curtain, horizontal focal plane
- Before 1959: 1/25, 1/50, 1/100, 1/250, 1/500 +B
- Since 1959: 1/30, 1/60, 1/125, 1/250, 1/500 +B
- Shutter release: on the top-plate
- Cocking knob: also winds the film, on the right of the tıop plate
- Frame counter: manual setting, on the cocking knob
- Viewfinder: SLR pentaprism
- Mirror: not instant return
- Film Loading: bottom loading, removable special take up spool
- Bottom plate opens by a folding lever on it
- Engravings around the opening ring: ЗAКР - ОTKP (Zakr- Otkr = Close - Open). ОTKP is an abbreviation for ОТКРЫТЫЙ
Notes and references
- Typing and info are as to Alexander Komarov
- Looks like M39 Leica mount but due to the mirror space, the rangefinder M39 mount lenses do not work properly on this camera. You can use them only the close-up focus range.