The Colored Shadows Wall is a discovery of the colors hidden in white light. Red, green and blue spotlights shine on a wall. The wall is white because red, blue and green light combine to make white light. These colors are often called the additive primary colors. As you walk between the lights and the wall, your body casts three different shadows. Wherever a shadow blocks one color of light, the other two colors combine to produce a new complementary color. By standing close enough to the wall, six different colors can be created, as well as black and white.