Similar to Technicolor, the Iriscolor process needed a special beam-splitter camera for exposing three black-and-white negatives on Kodak film stock. These negatives were used for imbibition printing.
Between 1940 and 1942, Tobis Tonbild-Syndikat AG financed the development of the process and adopted it for test purposes, estimating it to be a potential competitor to the Agfacolor negative-positive process. Some allegedly satisfying test footage was shot including exterior shots of Berlin and Potsdam as well as animation. However, cooperation was aborted when the inventors did not agree to give up the foreign rights to Ufa Film GmbH.
Physician Franz Noack was supposedly the main inventor of the Iriscolor process. One of his business partners was veteran color-film cameraman Gotthardt Wolf who photographed the bigger part of all Agfa-bipack / Ufacolor films in the 1930ies and also worked at the Siemens color-film laboratories (Opticolor / Siemens-Berthon process).
In 1943, after the failure of negotiations with Tobis and Ufa, Franz Noack continued his color film research with the support of a NSDAP party office.
Original Technical Papers and Primary Sources
BArch / Bundesarchiv / German Federal Archives, R 109 I, 1180 and R 55, 1323.
Alt, Dirk (2011): “Der Farbfilm marschiert!”. Frühe Farbfilmverfahren und NS-Propaganda 1933-1945. München: Belleville, on p. 94. (in German)