Dyed Potato Starch Grains Produced This Color

Dancer wearing Egyptian-look costume with wings reaching to the floor
Originally uploaded by George Eastman House

"Auguste and Louis Lumière, inventors of the motion picture camera, also invented autochromes in 1904. The process used a screen of tiny potato starch grains dyed orange-red, green and violet. Dusted onto a glass plate, the dyed grains were covered with a layer of sensitive panchromatic silver bromide emulsion. As light entered the camera, it was filtered by the dyed grains before it reached the emulsion. While the exposure time was very long, the plate could be processed easily by a photographer familiar with standard darkroom procedures. The result was a unique, realistic, positive color image on glass that required no further printing." Check out Autochromes set on the George Eastman House flickr.
(Thanks, Mr. Powell)