Hand-colouring (or hand-coloring) refers to any method of manually adding colour to a black-and-white photograph, generally either to heighten the realism of the photograph or for artistic purposes. Hand-colouring is also known as hand painting or overpainting.
Typically, watercolours, oils, crayons or pastels, and other paints or dyes are applied to the image surface using brushes, fingers, cotton swabs or airbrushes. Hand-coloured photographs were most popular in the mid- to late-19th century before the invention of colour photography and some firms specialised in producing hand-coloured photographs.
Monochrome (black and white) photography was first exemplified by the daguerreotype in 1839 and later improved by other methods including: calotype, ambrotype, tintype, albumen print and gelatin silver print. The majority of photography remained monochrome until the mid-20th century, although experiments were producing colour photography as early as 1855 and some photographic processes produced images with an inherent overall colour like the blue of cyanotypes.
In an attempt to create more realistic images, photographers and artists would hand-colour monochrome photographs. The first hand-coloured daguerreotypes are attributed to Swiss painter and printmaker Johann Baptist Isenring, who used a mixture of gum arabic and pigments to colour daguerreotypes soon after their invention in 1839. Coloured powder was fixed on the delicate surface of the daguerreotype by the application of heat. Variations of this technique were patented in England by Richard Beard in 1842 and in France by Étienne Lecchi in 1842 and Léotard de Leuze in 1845. Later, hand-colouring was used with successive photographic innovations, from albumen and gelatin silver prints to lantern slides and transparency photography.