a new type of roll-film camera. However, the company rejected his proposal because they thought there would be problems keeping the film perfectly flat. Besides, their current camera range, which used conventional photographic plates, was selling well. Heidecke tried unsuccessfully to secure financing to start his own company, so, at the insistence of his wife, he presented his concept to , a salesman and former colleague at Voigtländer. Franke was so enthusiastic he put up 75,000 M of his own money and went looking for more capital. After he secured additional funding of 200,000 M, they resolved to go into business together. In November 1919, they filed an application to register the company "Franke & Heidecke", which was entered into the German Trade Register on 1 February 1920. In need of factory space, they rented several rooms in a house at Viewegstraße 32, which became the companies first headquarters. The house survived World War II intact and stands to this day. Other rooms in the house were used by a dancing school, who had to abandon their dancing lessons because of noise from the factory. Within a year, Franke and Heidecke had taken over the entire building. By 1922, business was so good that they were able to take out a loan to purchase the property outright. Stereo Heidoscop To get the company going, Franke and Heidecke decided to manufacture a stereo camera in the short term. Cameras of this type were popular, and Reinhold Heidecke was very familiar with them. As they were also in Voigtländer's product range, however, Franke and Heidecke did not want to look as if they were simply copying theirs. They purchased several Voigtländer units, and from what they learned by dismantling these, constructed the Stereo Heidoscop. It included two Carl Zeiss Tessar lenses (f/4.5, 55 mm) and, mounted between them, a Carl Zeiss Super Triplet (f/3.2) viewfinder. At that time, Tessar lenses were widely regarded as the best available; they were often used in the United States, even though locally produced alternatives were available. Zeiss had an excellent reputation world-wide, which Franke & Heidecke leveraged for their own products. More importantly, they differentiated themselves from cheaper alternatives. The camera projected an image onto glass plates of dimensions 45 mm x 107 mm. The name Heidoscop was chosen in part to remind the management at Voigtländer that they had restricted Heidecke in his work there.