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When you look at color in the real world, you're seeing the real thing: the full spectrum of color, from red sunsets to purple mountains plus all the colors of fire engines, new Volkswagen Beetles, and the grassy and flowering plains in between. When you look at mechanized color images, however, from printed pictures to TV and computer screens, the colors you see are almost always an illusion!
Understanding why the trick works
Although printed or displayed color images seem to be using a full range of colors, they really use a mix of just three (or, in print, four) colors. They can get away with this trick because your eyes have just three kinds of color sensors: one kind that is most sensitive to blue, another that is biased toward red, and a third that favors green. If truly yellow light from the real world strikes your eye, it has an energy partway between red and green, so it tickles both the red and the green sensors by certain amounts. Your brain says "Aha! Red and green: It must be yellow!"
PC and TV screens use this trick to create the illusion of colors, like yellow: Each pixel on the screen is made up of a red, blue, and green glowing dot, the brightness of which is adjustable. The PC turns the blue way down, cranks up the red and green, and you see yellow because your red and green sensors are tickled equally. To get gray, all three colors are made equal; to make white, they're all at full strength; and to make black, they're all zero. But it's all an illusion. Your PC screen cannot really make yellow, orange, magenta, or anything other than pure red, green, and blue.
Fiddling with the mix
To make use of this inside information to adjust the mix of primary colors, start with the Materials palette. Whenever you're choosing a color in the Available Colors area, the primary color values (labeled R, G, and B for Red, Green, and Blue) appear at the bottom of a box that follows your cursor around. (In fact, RGB values for colors appear all over Paint Shop Pro.)
Simply knowing this color's number isn't particularly helpful; but now that you know what these numbers mean, you can use them to fine-tune the color by using the Material dialog box.
To bring up that dialog box so that you can precisely change your foreground or background material, click the Foreground Material or Background Material square on the Materials palette. A Material dialog box appears, and in that box is a Color tab.
You can fiddle with the color by changing the values for R, G, and B, as described in these examples:
- Need a more pastel shade? Decrease the highest value and increase the lower values.
- Need a purer color? Decrease the lowest of the three values.
- Need a darker or lighter shade? Decrease or increase all three values, keeping the same proportions of each one. White occurs when all values are 255. Black occurs when all values are zero.
- Need to move a color toward a given primary color (to make a greener yellow, for example)? Increase that primary value (in this instance, green); decrease the next largest value proportionately to keep the lightness the same.
Of course, you can skip all this by-the-numbers stuff and just click the color you want, but sometimes being precise is useful. You can paint more convincing shadows in outdoor scenes, for example, if you adjust all the values proportionately downward from whatever color you used for the sunlit side and then add just a little blue. (Light in shadows tends to come from a bluish sky.)
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