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Understanding Color

In This Chapter

 Getting the essentials of managing color

 Speaking the language of color

 Mixing three hues into millions of colors

 Choosing the right color mode for your image

 Switching between color modes

n order to manage and correct color photos, you need to understand a few

things about how your digital camera, your computer, and your printer

handle color. The tools you use to create your photos capture and display

color in a consistent manner. Although not the most exciting aspect of cor-

recting an image for proper color viewing, the basics of color and how your

devices deal with color is an essential ingredient to producing better

color photos. In this chapter, we cover some essentials of color

that you need to know as you work through all the other

chapters in this book.

Understanding Calibration Basics

Throughout this book, we talk about working in a

good color-management workflow. Developing such

a workflow begins with the essentials — setting up

your work environment, getting your monitor in

shape, and using your color desktop printer properly.

In this book, we talk about some sophisticated measures

to help you best view, edit, and print color images. In some

cases, you may think that some recommendations and tips we

offer are a bit more than you want to do when you edit your own pictures.

If you’re not ready to change your work environment, you need to make some

decisions about what you can realistically do to prepare your environment

and your computer as best you can to effectively edit photos.

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Summary of content (14 pages)

PAGE 1
AL Understanding Color In This Chapter Speaking the language of color Mixing three hues into millions of colors Choosing the right color mode for your image D I MA Switching between color modes TE RI Getting the essentials of managing color PY RI GH TE n order to manage and correct color photos, you need to understand a few things about how your digital camera, your computer, and your printer handle color.
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8 Part I: The Basics of Color Editing One thing to keep in mind is that the more preparation steps you cut out of your color-management workflow, the farther you move away from accurate color reproduction. Therefore, you may decide to eliminate some things that we consider critical to preparing your work environment; but realize that you can’t expect to achieve the most accurate color in your photos.
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Chapter 1: Understanding Color There you have it. Your first steps in color correction involve controlling lighting, calibrating your monitor, and having all the color profiles you need for editing images and outputting them either for Web hosting or printing. After you have these essentials in place, you can begin the task of color correction.
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10 Part I: The Basics of Color Editing Red Yellow (Red + Green) Magenta (Red + Blue) Green Blue Cyan (Green + Blue) Figure 1-1: This simple color wheel shows red, green, and blue hues. The first thing you might question is the yellow patch, made from green plus red. Keep in mind that you’re mixing light, not paint. Mix equal parts of red and green light, and you get yellow. No, we’re not making this up! Your eyes see yellow when something you’re looking at emits equal parts of green and red light.
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Chapter 1: Understanding Color 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.
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12 Part I: The Basics of Color Editing (a) Highly saturated (b) Less saturated than a a (c) Greatly desaturated b (d) Completely desaturated (no color) c Figure 1-2: A green patch shown at different levels of saturation. Figure 1-3: These three cyan color patches vary in brightness values, from least bright on the left to brightest on the right.
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Chapter 1: Understanding Color We repeat these color concepts a great deal in this book as we work our way through color management. Editing a file to change overall color, brightness, and contrast often affects the hue, saturation, and brightness of the colors in your file. Understanding how to define those changes can make the rest of the book far easier to understand. Color space Throughout this book, we continually refer to the term color space.
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14 Part I: The Basics of Color Editing Suppose you took a picture in which the foreground subject is in the sun. In the background, your eyes see a beautiful range of shaded trees. When you print your photo, the leaves on the trees aren’t completely visible. They look dark and don’t have much detail. The dark tones were clipped (cut off) from the image. Mixing Colors Your computer monitor is capable of displaying a total of 16.7 million distinct and individual colors.
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Chapter 1: Understanding Color 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.
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16 Part I: The Basics of Color Editing Understanding channels In Photoshop Elements terms, the three hues your monitor displays (red, green, and blue) are called channels. You can easily see the three channels by opening an RGB color image in Standard Edit mode and opening the Levels dialog box. Select Enhance➪Adjust Lighting➪Levels or simply press Ctrl+L (Ô+L for Macs). When the Levels dialog box opens, click the RGB menu (the down-pointing arrow), and you see the three channels, as shown in Figure 1-5.
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Chapter 1: Understanding Color Why are there 256 levels? This 256 number comes up a lot when talking about image modes. What makes it so special? Reproducing tone on paper or a monitor requires a minimum of about 200 tone levels to give smooth results without banding (or making sharp transitions between) the tones in smooth gradient image areas. Some images can get along with far fewer levels of tone, such as highly textured images or those that don’t really contain any smooth tones.
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18 Part I: The Basics of Color Editing color file sizes as small as possible. Computers couldn’t display 16.7 million colors back then, so monitors that showed images in only 8-bit mode used index color. Web pages still use index color today, in the form of GIF-format files that are limited to 256 colors. The Save for Web option in Elements allows you to save files in the GIF format, if you want.
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Chapter 1: Understanding Color CMYK You can’t edit in this mode, but Elements does allow you to open a CMYK color mode file that Elements converts upon opening to RGB mode so that you can work with the image. CMYK is the color mode used for traditional printing press reproduction of color images. For example, this book was printed from CMYK-mode files. Printing presses need to use four separate ink plates to reproduce full color images on paper.
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20 Part I: The Basics of Color Editing Grayscale mode has far more editing options than bitmap mode. It’s best to keep master files in grayscale mode and convert to bitmap mode as a final step before viewing or printing the file. If you want to convert RGB to grayscale, always convert a duplicate file. All the color information is lost when you convert a file to grayscale mode.