Fundamentals of Color Theory: Light and Pigment Mixing

1. Additive Color Mixtures (Light)

We can derive all colors from three primary colors of light: Red, Green, and Blue (RGB).

An additive mixture is created when colored lights are mixed, because we are adding light energy each time. Mixing two primary colors results in secondary colors:

• Blue Light + Green Light = Cyan Light
• Green Light + Red Light = Yellow Light
• Blue Light + Red Light = Magenta Light

When combining all three primary colors of light, the result is white light.

Color Descriptions in Additive Systems

In this context, blue refers to a more blue-violet color; red is often a red-orange; magenta is similar to fuchsia pink; and cyan is a bright blue.

2. Subtractive Color Mixtures (Pigments)

Color pigments, such as the paints used on paper, are made of colored powder mixed with various substances.

The three primary pigments, which cannot be created by mixing other colors but can be mixed to obtain all others, are Cyan, Magenta, and Yellow (CMY).

Mixing two primary pigments results in secondary colors:

• Cyan + Magenta = Blue
• Magenta + Yellow = Red
• Yellow + Cyan = Green

When we mix pigments, we are subtracting light, reducing the amount of light reflected back to the eye. When all three primary color pigments are mixed together, the result is black.

3. The Color Wheel

The color wheel is a tool used to organize colors according to their changes in hue. It starts with one color, transforms gradually into the next, and finally returns to the starting color.

Historically, the Red-Yellow-Blue (RYB) color wheel was commonly used. However, as technology has advanced, particularly in the printing industry, the CMY (Cyan, Magenta, Yellow) color wheel is now standard for pigments.

Color Categories on the Wheel

• Primary Colors: Colors that cannot be created by mixing other colors.
• Secondary Colors: Colors obtained by mixing equal amounts of two primary colors.
• Tertiary Colors: Colors resulting from the mixture of one primary color and an adjacent secondary color.

4. Color Scales and Complementary Hues

Complementary Color Sets

Complementary colors are pairs of colors with opposite hues on the color wheel. A primary color is complementary to a secondary color if it is not part of that secondary color's mixture.

When complementary pigments are mixed together, they theoretically produce black (due to the subtraction of all light).

Complementary color pairs are those that do not share any common primary colors in their composition. They appear directly opposite one another on the pigment color wheel (CMY/RYB).

Common Complementary Pairs (Pigments)

• Red – Green: (Green is Blue + Yellow, which does not contain Red.)
• Blue – Orange
• Yellow – Violet