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Q & A: Describing color.

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Most recent answer: 01/17/2013
How can you describe a color?
- Dakota (age 13)

Hi Dakota,

We see objects because our eyes sense the light an object reflects. This light is made of electric and magnetic waves which oscillate, or wiggle back and forth, like waves in water. The distance between two peaks on this wave is called the wavelength. All the colors in the rainbow, and many other "colors" that we cannot see, like ultraviolet and infrared, have slightly different wavelengths. This is a very precise way to describe their colors.

However, not all colors have their own specific wavelength. Instead, colors like brown and pink are made by mixing light of more than one wavelength. What we see as white light, for example, is a mix of all the other colors. The standard way to describe how our brain sees a color is to list its hue, saturation, and luminosity. Hue, or tone, is what we usually mean by "red," "green," "blue," etc. Saturation refers to how pure a color is; to make it less saturated/pure, you just add gray. The luminosity of a color just describes how much total light there is. A good picture of how this works can be found at

Hope that helps,
David Schmid

(published on 01/17/2013)

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