Preparing the Image

Here's the best strategy if you know you'll want to print your final Photoshop image: Keep the printer in mind throughout the entire process! Different printers output differently, so knowing your printer enables you to adjust your image for its particular behavior and, thus, guarantee the best possible image on the final printed page. This is particularly true for full- color images.

With that in mind, always configure Photoshop for the monitor and printer you'll be using, and do so before even considering printing anything important! This configuration involves several different areas: setting up monitors , printing inks, separations, and separation tables.

Color management capabilities have become an important feature in Photoshop, and are managed by a collection of predefined settings for monitors and printers, and even print media. Each setting includes a corresponding color profile and conversion options, which should give you consistent color for a particular kind of printer under typical conditions. Color management is most helpful if you output your work to several printers or different kinds of printers, such as laser and imagesetter, or if your images will appear on the Web as well as in print and keeping the colors consistent from one kind of output to another is important to you.

What's Color Management?

Color management is what enables you to move color information from one device (such as a monitor) to another (such as a printer) in a predictable and measurable manner. This is what's meant by WYSIWYG color: What You See (on the monitor) Is What You Get (when the image is printed). It's not automatic.

For many printers, scanners , and monitors, color management is handled by International Color Consortium (ICC) profiles. These are made by measuring each device in accordance with a language agreed upon by the ICC (a consortium of color management professionals and vendors ). To create an ICC profile for a printer, the profiling software includes a target chart with many small squares of color. The target is printed on the printer being profiled. Then, a measuring tool is placed over each of the color squares and a measurement is taken. The data goes back to the computer, which compares the printed colors against the theoretically perfect colors of the software target and defines the differences. These are all assembled and calculated, and an ICC profile for that printer, ink, and paper combination is produced. The profile is actually a set of numbers that tells the computer how to adjust the color information it sends to that particular printer to make the printed colors match as closely as possible the colors in the image file. Scanner profiles are produced by scanning a known color chart, and monitor profiles are created by displaying the chart onscreen and measuring the color squares with a tool similar to the one used for the printed chart.

ColorSync is color management software developed jointly by Apple and Linotype-Hell. ICM is a similar program for Windows. They are used to correct color spaces for both display and print. ColorSync and ICM include profiles of many kinds of monitors, so you can select yours or at least one close to it. They adjust color on the monitor so that printer color space (CMYK) is displayed correctly.

What does all this mean to the novice user with a home-quality inkjet printer? Here are a few suggestions:

• Do your work in RGB color. If you have ColorSync available, be sure that you've set it to your own monitor. If you don't have it, use Adobe Gamma (Windows) or Display Calibrator Assistant (Mac OS X). Adobe Gamma is a control panel that comes with Photoshop to let you adjust your monitor according to how it displays colors, and Display Calibrator Assistant is a similar program that's built in to the Mac OS.

• If you're printing to a low-end printer, don't convert the color to CMYK. Photoshop will make the conversion as it sends the data to the printer. It actually does this quite well.

• If you'll be printing on a machine that has an ICC profile, change the file color space to CMYK when you're ready to save it for printing, and apply the ICC profile. (Be sure to save an RGB copy, too.)

Figure 23.7 shows the Color Settings dialog box. You can find it on the Edit menu, or you can press Command+Shift+K (Mac) or Ctrl+Shift+K (Windows) to open it. Be sure to notice the descriptions area at the bottom of the dialog box. It can be very helpful when you're not sure which settings to use.

Figure 23.7. The default color settings are for images that may be both printed and displayed on the Web.

As you can see, you need to make several decisions, even without shifting to the Advanced mode. First, you need to use the Settings pop-up menu, shown in Figure 23.8. You need to decide whether Color Management should be on or off. If you turn it off (click More Options to see this choice in the menu), you're not left colorless. Photoshop will still apply minimum color management standards to make the color onscreen match that of noncolor-managed documents. It's most useful for onscreen presentations.

Figure 23.8. Choose an appropriate setting.

If you know that your work will be printed on standard printing presses (not a home inkjet), apply either the U.S., European, or Japanese standard prepress defaults according to where your printing company is. (It's not uncommon for some artists and ad agencies in the U.S. to send high-quality print jobs to another country where they can be done less expensively.)

Customize It

You can also save and load various combinations of settings you create via the Save and Load buttons , respectively.

Working Spaces

The Working Spaces settings in the Color Settings dialog box are less complicated than they look (which is nice for a change). RGB asks for the monitor space you want to work in. Choose sRGB if you plan to share your images mostly onscreen, as web images or via email or slideshows; sRGB is a version of RGB that includes the colors that the standard computer monitor can display. If you will be printing most of your images, on the other hand, stick to Adobe RGB; it includes some printable colors that don't show up in sRGB.

The CMYK field wants you to choose the kind of printer you're using. Again, if it's all Greek to you, choose Generic.

Gray is easy. If you use a Mac, choose Gray Gamma 1.8. If you have a PC, choose 2.2. These are the basic settings for the method that each system uses to display grayscale images.

Spot refers to pages printed with black and one or two spot colors, such as duotones, or illustrations done with black and white and limited PANTONE colors. The standard setting is Dot Gain 20%.

Color Management Policies

The Color Management Policies refer to how Photoshop handles files created in another application or in an earlier version of Photoshop. Your choices are to preserve the color management profiles embedded in the file, convert to your active mode, or turn off color management. This last choice lets Photoshop display the file in Active mode, while keeping the embedded profile, until you resave it with the new color management information. You can also direct Photoshop to warn you when a color management mismatch occurs as you open a file and ask what to do about it. Figure 23.9 shows a typical warning message.

Figure 23.9. This happened because I opened an image created in an older version of Photoshop.

Conversion Options

If you check Advanced mode, you'll have additional choices to make. The first of these is Engine, which refers to the color conversion engine that Photoshop uses to match colors. Even if you're using a Mac, ignore the Apple ColorSync option and choose Adobe (ACE). It's designed specifically to work with Photoshop and other Adobe graphics applications. For Intent, unless you need to match another version of the image exactly, I suggest you use Perceptual. It will give you the most pleasing colors, rather than the most mechanically accurate ones. It also allows you to print a wider range of colors than, for example, Absolute Colorimetric. Check both Black Point Compensation and Use Dither, unless your print shop or service bureau tells you not to. Again, you'll see better-looking color.

However, you can usually ignore the Advanced Controls area. You don't want to desaturate your monitor or change the color-blending gamma except under rare circumstances, which is something only an expert user is likely to encounter.