The reflex camera

The principle of the reflex camera made viewing possible through the lens, in other words the exact view of what one is going to photograph. The first reflex cameras appeared around 1890. The small format reflex appeared towards the end of the 1930s, and became more and more successful.

The main advantages of reflex viewfinding, in terms of focusing in macrophotography for instance, prompted manufacturers to integrate it within small and medium format cameras of the 1930s. The Спорт (Sport), made in Russia around 1935, was allegedly the first small format reflex camera on the market. This new reflex generation still had a major drawback: the viewing was obscured, when the diaphragm was shut to take the photograph.

Around 1935 a Swiss precursor, Jacques Boolsky, designed a small format reflex camera, and entrusted Pignons S.A. of Ballaigues in the Vaud Jura region with its research and manufacturing. Combining reflex viewfinding and a telemetric viewfinder, this camera was released in different versions from 1939, and the final version was eventually presented at the Basel Sample Fair in 1944, and marketed as the Alpa Reflex I.

Illustration:
Cross-section of a Praktica IV SLR camera, K.W., VEB Pentacon, Germany, 1959-1964.