The world is a colourful place, but it would be several decades before this was properly represented in photography. Léon Vidal was one of the pioneers of colour photography. In 1872 he registered his photochromy technique in Paris. In this highly elaborate photomechanical printing method, which requires several black-and-white negatives, colour is added in the final stages of the production process. This photograph shows a masterpiece of goldsmithery, a sixteenth-century dagger, against a blood-red background.