Autochrome
The first commercially successful colour process, using a screen of dyed potato starch grains over a black and white emulsion.
In depth
Introduced by the Lumière brothers in 1907, the plate carried millions of microscopic starch grains dyed orange, green and violet, acting as a random colour filter array — conceptually the direct ancestor of the Bayer filter. Results are soft, pointillist and richly coloured, and required exposures many times longer than monochrome.
Examples in practice
An Autochrome portrait from 1910 shows delicate, granular colour with an almost impressionist surface texture.