A Dufaycolor colour transparency of a Dufay Limited delivery van, taken by an unknown photographer in about 1950. This Humber delivery van is painted in the yellow, black and red colours of Dufay Limited.

The Dufaycolor process was introduced as cine film in 1932 and as rollfilm for still photography in 1935. Based on Frenchman, Louis Dufay's (1874-1936) Dioptichrome process of 1908, it was the last 'additive' colour process to be marketed. Dufaycolor consisted of a very fine, regular filter screen made up of red, green and blue lines printed on a film base. It was popular with both amateur and professional photographers and survived until the 1950s.