Chiaroscuro

Chiaroscuro (English pronunciation: /kiˌɑːrəˈskjʊəroʊ/; Italian: [ˌkjaroˈskuːro] (light-dark)) is an oil painting technique, developed during the Renaissance, that uses strong tonal contrasts between light and dark to model three-dimensional forms, often to dramatic effect.

The underlying principle is that solidity of form is best achieved by the light falling against it. Artists known for developing the technique include Leonardo da Vinci, Caravaggio, and Rembrandt. It is a mainstay of black and white photography.

Chiaroscuro originated during the Renaissance as drawing on coloured paper, where the artist worked from the paper's base tone toward light using white gouache, and toward dark using ink, bodycolour or watercolour. These in turn drew on traditions in illuminated manuscripts going back to late Roman Imperial manuscripts on purple-dyed vellum. Such works used to be called "chiaroscuro drawings", but are more often described in modern museum terminology by such formulae as "pen on prepared paper, heightened with white bodycolour". Chiaroscuro woodcuts began as imitations of this technique. When discussing Italian art, the term sometimes is used to mean painted images in monochrome or two colours, more generally known in English by the French equivalent, grisaille. The term broadened in meaning early on to cover all strong contrasts in illumination between light and dark areas in art, which is now the primary meaning.

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