The Three-colour Process

Isaac Newton’s 17th century experiment with a prism that proved sunlight comprised of seven colours was essential to the development of colour photography. To accurately reproduce colours required a keen understanding of the nature of light. Centuries later, James Clerk Maxwell was able to demonstrate that through mixing red, green and blue light, all colours could be replicated. He made three different
magic lantern slides of a tartan ribbon, each with a filter of one of the primary colours. Then, by carefully superimposing the slides onto each other, he was able to get a coloured image of the object. Called the three-colour method, Maxwell had published his ideas in 1855, and Thomas Sutton demonstrated it for an audience in 1861. Maxwell won the Royal Society’s Rumford Medal for his work on colour.