Datasheet

The next color that might confuse you is blue. It looks purple, you say? You

also might think that the cyan patch should really be called blue. Remember,

you’re mixing light, not paint.

Your kindergarten teacher is probably to blame for the confusion. Back when

you mixed paints in those long-ago classes, she showed you that blue and

yellow mixed together made green, and you probably had a pot of paint called

purple that looked like the blue patch on our color wheel.

Mixing paints to get different colors uses subtractive primaries. The subtrac-

tive primaries are cyan, magenta, and yellow. Your teacher probably called

them blue, red, and yellow. It made naming the paints a lot easier, but it

wasn’t really correct.

Equally mixing the red, green, and blue primaries create cyan, magenta,

and yellow on your monitor, as shown on the color wheel in Figure 1-1. Just

remember that you need the basic hues of red, green, and blue to make a full

range of hues (or colors) on the computer.

Colors exactly opposite of each other on the wheel are called

complementary

colors.

Mix the complementary colors together on the monitor in equal parts,

and you get a shade of gray, light gray, or white. The complementary colors

cancel each other out. We talk more about this concept of colors canceling

each other out in Chapter 8, where we show you how to correct the color on

a bad image file.

Saturation

The term saturation defines the purity of a hue. Saturation is pretty easy to

understand if you look at a few examples, such as the ones shown in Figure 1-2.

The green patch in Example A is a highly saturated hue. In Example B, the

patch is the same hue but less saturated. In Example C, the patch is desatu-

rated more than B. Finally, in Example D, you see the same hue completely

desaturated and therefore devoid of color.

Saturation defines the vividness of the hue in question. Think of a desatu-

rated color as one with white, gray, or black mixed in. Gray represents a fully

desaturated tone — no color at all.

Brightness

Brightness means what it says: It’s the term used for how light or dark is the

hue in question. Keep in mind that a hue can be bright without being satu-

rated. Here’s an example: The three cyan patches in Figure 1-3 are equal in

saturation, but they vary in brightness.

Chapter 1: Understanding Color

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