Understanding Color Systems


Understanding Color Systems

You've learned how to open files, and although we haven't talked much about how to improve your photos yet, you know how to import them into Elements and make a few changes, so you're probably eager to print them and show them off. In this section, you'll learn everything you need to know about printing, starting with color systems and how they relate to preparing and printing images.

When it comes to printing color, there are many models you can use to specify the colors to print. Naturally, because there are thousands of colors visible to the human eye, it's difficult for any color system to accurately reproduce them all. If printing a color photograph is your goal, your result will depend on the color system you choose to display, save, and ultimately print your image with.

RGB

RGB (short for Red, Green, Blue) uses a system that defines a particular color by the amount of red, green, and blue it has in it. If you mix all three colors in equal amounts, you get white. If you don't add any of them, you get black. Computer monitors , television sets, and Photoshop Elements use the RGB system to define and display the colors you see onscreen.

Typically, a scale from 0 to 255 is used to specify the amount of each color (red, green, and blue) that exists in a particular color you're looking at. You may have noticed that when you open the Color Picker, instead of clicking on the color you want, you can define it by typing in the appropriate formula ”the amounts of red, green, and blue in the color.

graphics/bookpencil_icon.gif

Closely related to the RGB color system is CMYK, short for Cyan, Magenta, Yellow, Black. When you mix cyan, magenta , and yellow in equal amounts, you get black. If you don't add any of them, you get white. CMYK is also known as the four-color process, and it's used by many computer printers and professional four-color printers. Unfortunately, Elements does not support this system ”but that shouldn't matter too much, because if you want to print in four colors (which is expensive) it's probably because you want to produce a nice-looking color brochure, sales catalog, or similar project, and the program you use to create such a project will certainly support CMYK.


HSB

The Hue, Saturation, Brightness (HSB) model is mathematically similar to the RGB model ”it produces the same number of colors, but in a different way. The hue value specifies the color, such as red. The saturation value specifies the purity of the color ”a lower saturation value gives you a more grayed-out version of your hue ”in this example, a more grayed-out red. The final value, brightness, specifies the amount of whiteness in the color; in other words, how light or dark the red is. Brightness is sometimes also called luminance, value, or intensity. You might have noticed the Hue, Saturation, and Brightness boxes in the dialog box for the Color Picker. You can use these values rather than the RGB values to specify the exact color you want.

Pantone Color Matching System

With the Pantone Color Matching System, values are not needed. Instead, the system uses a series of color charts and accompanying print formulas to assure a designer that the color he chooses from a chart will be reproduced exactly. This system is often used to recreate colors critical to a printout ”typically, a signature or logo color. All a designer has to do is select a color from a Pantone Color chart, and then specify the number of that color on the order form, or within the software program generating the image ( assuming the program supports the Pantone system). If needed, you can use this system as well ”Elements provides a place in the Color Picker dialog box for entering the Pantone color desired.



Sams Teach Yourself Mac OS X Digital Media. All In One
Sams Teach Yourself Mac OS X Digital Media All In One
ISBN: 0672325322
EAN: 2147483647
Year: 2003
Pages: 349

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net