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Appendix A - Identifying the Kurt Franz Camera

Appendix A - Identifying Kurt Franz Camera

The confident identification of existing buildings imaged on both ground and aerial photos required triangulation to pinpoint the position from which the terrestrial pictures were taken and the angles to the various buildings visible from ground and air stations. For this, a knowledge of the type of handheld camera used is required as well as its nominal focal length, its field of view (Fov), and the format of the film used. Several makes of German cameras produced in the era between 1930 and 1943 were considered. The cameras surveyed are shown in the table below.

Camera Model/Year Lens FoV Film Format
Leica/1930 Hector 50mm f/25 37.6 degrees 35mm film - 24 x 35mm
Voightlender Bessa/1936. Folding Belows 105mm f/2.8 46.4 degrees and 24.2 degrees 120 film with two options: 90 x 60mm or 45 x 60 mm
Kodak Retinette/1939 45mm f/2.8 40.7 degrees 35mm film - 24 x 35mm
Minox/1938-43 15mm 40.1 degrees 8 x 11mm
Table A1 - Candidate Cameras Evaluated

The Leica inclusion afforded a generic type for all 50mm focal length, 35 mm film cameras. The other cameras included a variety of formats. The Minox was produced for the German army in WWII. The Voightlander and the Retinette covered commonly produced cameras available to the German public. Of these cameras, analysis showed that only one could have been the instrument used by Kurt Franz: the Voightlander Bessa, a bellows type camera with a relatively long nominal focal length of 105mm. The Voightlander had two modes of operation: one could expose eight 90 by 60 millimeter pictures, or sixteen 45 by 60 millimeter frames. Analysis revealed that the Franz photographs were exposed in the smaller format.

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