thumb|A home-processed Dufaycolor 6x6 cm Reversal film|transparency, 1956|alt=An elderly man, wearing a grey coat and holding a black hat sits in a garden in autumn.
thumb|A home-processed Dufaycolor 6x6 cm Reversal film|transparency, 1956|alt=An elderly man, wearing a grey coat and holding a black hat sits in a garden in autumn.
Dufaycolor is an early British additive colour photographic film process, introduced for motion picture use in 1932 and for still photography in 1935. It was derived from 's Dioptichrome plates, a glass-based product for colour still photography, introduced in France in 1909. Both Dioptichrome and Dufaycolor worked on the same principles as the Autochrome process, but achieved their results using a layer of tiny colour filter elements arrayed in a regular geometric pattern, unlike Autochrome's random array of coloured starch grains. The manufacture of Dufaycolor film ended in the late 1950s.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).