Much of the impact of an image comes from its manipulation of lighting. In cinema, lighting is more than just illumination that permits us to see the action. Lighter and darker areas within the frame help create overall composition of each shot and thus guide our attention to certain objects and actions. A brightly illuminated patch may draw our eye to a key gesture, while a shadow may conceal a detail or build up suspense about what may be present. Lighting can also articulate textures: the curve of the face, the grain of a piece of wood, the tracery of a spider’s web, the sheen of glass, the sparkle of a gem.
Lighting shapes objects by creating highlights and shadows. A highlight is a patch of relative brightness on a surface. Highlights provide important cues to the texture of the surface. If the surface is smooth, like glass or chrome, the highlights tend to gleam or sparkle; a rougher surface, like a coarse stone facing, yields more diffuse highlights.