Directional Light on Film: The Foundations of Depth, Shape, and Tonal Control (Part I)

Chiaroscuro is the controlled use of directional illumination to create depth, dimensionality, and tonal separation inside a portrait. The term is sometimes used loosely to describe dramatic or shadow-heavy images, but that simplification does not describe its real function. Chiaroscuro is not an effect. It is not an aesthetic layer applied to an image. It is a precise lighting system that defines the physical structure of a portrait through the relationship between illuminated planes and shadow planes.