additive

Color Theory	Color Schemes	Psychology of Color

Additive Primaries	Warm and Cool Colors	Colors and Moods
Subtractive Primaries	Analogous	Colors that Move
Hue	Complementary	What To Avoid
Shade	Monochromatic
Tint	Triadic
Saturation
Mode

What are additive primary colors?

The color wheel looks like blocks of solid color. In actuality the color wheel is millions of colors that are blended into one another as you move around the color wheel. Some colors are solid and some are blended.

We see with our eyes the colors created by the natural light in the world. These colors are known as additive colors. The term "additive" refers to the mixing of light.

When equal amounts of red light, green light, and blue light are mixed together they produce white light. Because you add the colors together to get white we call these the additive primaries.

If one of the additive primaries are removed, the color of the light changes. For example, if the red light were removed, equal amounts of blue and green light would make cyan light. Equal amounts of green and red light would make yellow light, and equal amounts of red and blue light will make magenta light.

The absence of all light also means the absence of all color, creating black.

We can observe additive color when we see a rainbow form from light diffracted through a prism, or when we use RGB setting to create color in computer software programs like Photoshop^® or Illustrator^®.

Note: You may have noticed that some of the above information seems to contradict what you were taught as a child. Aren't the primary colors red, blue, and yellow? Don't red and green together make purple? If you mix the three primaries, don't they make black? Yes, all this is true, IF you are using paint or crayons to create your colors. When you mix color pigments, you are working with subtractive colors, which don't behave the same way as additive colors. See Lesson 2 for more information on subtractive colors.

RGB is the acronym which stands for red, green, and blue. All color computer monitors are RGB monitors.

The web site www.webopedia.com describes how RGB monitors work: "An RGB monitor consists of a vacuum tube with three electron guns -- one each for red, green, and blue -- at one end and the screen at the other end. The three electron guns fire electrons at the screen, which contains a phosphorous coating. When the phosphors are excited by the electron beams, they glow. Depending on which beam excites them, they glow either red, green, or blue. Ideally, the three beams should converge for each point on the screen so that each pixel is a combination of the three colors."