Color photography was born on this day 150 years ago in 1861 when Scottish physicist and mathematician James Clerk Maxwell and photographer Thomas Sutton — inventor of the SLR camera — shot the above photograph of a colored ribbon.
[...] Maxwell proposed that if three black-and-white photographs of a scene were taken through red, green and violet filters, and transparent prints of the images were projected onto a screen using three projectors equipped with similar filters, when superimposed on the screen the result would be perceived by the human eye as a complete reproduction of all the colours in the scene.
During an 1861 Royal Institution lecture on colour theory, Maxwell presented the world’s first demonstration of colour photography by this principle of three-colour analysis and synthesis, the basis of nearly all subsequent photochemical and electronic methods of colour photography. Thomas Sutton, inventor of the single-lens reflex camera, did the actual picture-taking. He photographed a tartan ribbon three times, through red, green and blue filters. [...] Because Sutton’s photographic plates were in fact insensitive to red and barely sensitive to green, the results of this pioneering experiment were far from perfect. [#]
Thus began modern color theory and the fundamentals behind how your DSLR captures color.
(via Popular Photography)