The painting below shows a warrior standing on a ledge. He is lit by a slanting bar of light that shines from below.
Note that the cast shadow from his arm is red on the bottom and blue above.
The colored shadows suggest that the scene is lit by two adjacent spotlights, a red one below and a blue one above. This is typical of theater lighting, where two or more colored spotlights cast shadows with chromatic edges.
Tomorrow we’ll take a closer look at chromatic shadows.
I painted the image for "Witches of Kregen," 1985, Daw Books. The painting will also appear in Color and Light.