The first 35 mm reflex camera invented
The single-lens reflex (SLR) techniques are prior to the development of photography, and have been used in art studios to project an image onto a transparent surface for tracing. While there are a number of obvious advantages to using a prism and a mirror to make a single SLR camera lens (especially being able to use a viewfinder that uses the current optical camera) the first 35mm SLR camera was not made until the 1930s, by GOMZ of Leningrad (today St. Petersburg).
The Sport uses a vertical metal door for the single-lens reflex lens, and mounts preset shutter speeds of 1/25, 1/50, 1/100, 1/200 and 1/500 seconds, plus a focal length 3.5 / 50 of the lens called “Industar-10”. Its dimensions are 133 mm high by 102 mm wide by 69 mm deep, with a weight of about 29 ounces (822 grams). The camera had rounded edges and a rather distinctive case assembly for the viewfinder.
Handling the film
The film cartridge for the Sport was a length of two meters of film, with 50 shots. Advance the film from left to right, and loading is done by opening the back of the camera. The film cartridges did not have a leader of pre-exposed material, so the load of the Sport is somewhat complicated for modern enthusiasts. The area of the negative is a frame of 24 mm by 36 mm.
For the Sport camera, the lens is mounted on a bayonet mount, and the controls for advancing the film were on the left side of the main body of the camera. The shutter speed adjustment dial was at the top right of the structure. There was also a viewer at the top of the camera, to work from the mirror and the prism of the real mechanism. There was a manual focus ring on the lens assembly.
Although there were competitors of the GOMZ camera, the 35mm SLR camera was something of a historical rarity through the 1950s. The competition of rangefinder cameras dominated the market due to its faster shutter speeds, the SLR cameras were smaller and portable. It was not until the 1970s and the advent of reflex autofocus cameras that they achieved their current dominance in photography.
- Rick Soloway: Timeline of the origins of photography
- Photohustory: The “Sport” camera of 1935
- Taunusreiter: History of the first single-lens reflex cameras