Subtractive Primary Colors
Subtractive Primary Colors are the three colors in the visible light spectrum that are produced when either red, green, or blue light is absorbed or subtracted and the unabsorbed colors are reflected or transmitted. These primary colors produce black when added together, unlike Additive primary colors that produce white when added together. The three subtractive primary colors are cyan, magenta, and yellow. Subtractive colors are pigments or inks being used on a sheet of paper and are not being produced by light like Additive primary colors. These colors are said to be subtractive because they absorb certain wavelengths of light while reflecting others, thus subtracting colors from the original light source. For example, an object that appears red is reflecting red light but absorbing all colors of different wavelengths in the visible light spectrum. Pigments of cyan, magenta and yellow can be mixed in different proportions to produce any hues of color. Cyan and magenta mix to reflect blue light. Cyan and yellow mix to reflect green light. Yellow and magenta mix to reflect red light. Equal amounts of each of the three primary colors results in black, because all wavelengths of light within the visible spectrum are absorbed.
- Judith A. Tyner, Principles of Map Design, New York: Guilford Press, 2010.