Dufay type: 3 colour analysis on single film in discrete areas / additive projection via original filter mosaic or optics.

Several additive systems involved the use of a mosaic [termed a reseau in Dufay] of red, green and blue filter patches on the emulsion surface or in the lens system, exposing discrete separation images relating to each patch. In Dufay, the patches were lines and squares of filter on the film emulsion, in lenticular Kodacolor the lines were created from the lens system. Reversal processing and projection through the original or similar filter patches yielded a colour image not unlike colour television. Negative positive systems existed as well although printing was complex in order to avoid interference patterns from the filter mosaics.