The discovery of colour film /…/ remains a challenge for the future. Mroz is convinced that sooner or later he will succeed in making this discovery.” In 1931, the technician and tinkerer Josef Mroz introduced a colour system for the 9.5mm format. It was a time when colour film stock was still in its vibrant phase of development. “Mroz-Farbenfilm” was not a new invention, but a rediscovery and an adaptation of the Biocolor process: The black and white film had to be exposed through red and green filters, and the film stripe itself was coloured by a machine alternating red and green dyes. During the projection, the flashing red and green images become colours in the viewers’ eyes and mind, thus revealing the imaginative capacities of film. Mroz’s additive two-colour system remained a Viennese phenomenon.

The integral version of this article can be found in the printed KINO!