The Perception of Color at Dawn and Dusk

The illumination of scenes by sunlight at dawn and dusk creates a rich array of colors and long high contrast shadows that make the appearance of the scene more beautiful and allow for better photographic imagery. Photographers often refer to this as when 'the light is right' as opposed to mid-day illumination when the light is 'flat and uninteresting'. When the light of the setting sun illuminates an object or person the surfaces impart a characteristic warm glow - the warm colors of the scene can almost appear self-luminous. This paper addresses this sensation with respect to color constancy, color appearance, chromatic adaptation, and digital photography. Because photographers strive for this kind of illumination it is vital that in the design of a color model for a photographic system that we understand and preserve the photographer's control of this effect.