Datasheet

Figure 1-4: The Color Picker identifies a fully saturated red color.
Understanding grays
The number of distinct settings you have for color mixing are commonly
called
levels of gray. Because the computer monitor doesn’t have a diaphragm,
you need some method for controlling the amount of light that passes
through any one of the three RGB phosphors.
Try to visualize a large plate of glass. If you paint the glass solid black and
place a light behind the black glass, zero light passes through it. If you then
paint a glass plate 50 percent gray, some light passes through the glass. As
you reduce the level of gray to smaller percentages, more light passes
through the glass, resulting in more saturated color.
Hence, in Photoshop Elements terms, you have 256 levels of gray that permit
you to increase or decrease the saturation on the three individual hues.
Remember when we said that your computer monitor can display 16.7 million
distinct colors? We got this number by multiplying the maximum number of
grays for each hue together (256
× 256 × 256 = 16.7 million). This number
really means that you have 16.7 million combinations of levels of gray with
which you can create colors.
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Chapter 1: Understanding Color
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