by Steve Bain
Trying to achieve consistent color across multiple devices connected to your computer can still generate its share of head-scratching, hair-pulling, and, yes, even the odd expletive. The truth is, a completely flawless method of desktop color management doesn't yet exist, although some systems come close. If you're a CorelDRAW Graphics Suite 12 user tackling color management for the first time, or just curious about how it's supposed to work, you've come to the right place.
Why Should You Use Color Management?
To illustrate why color management is important to anyone working in color, let's look at a typical scenario that you may have encountered. You scan an image or take a digital picture, open it on your computer, and then print it from your desktop printer. At each step in the process, you notice slight differences in color. This means that the colors in your final printed output may not exactly match the original you scanned. Now that we've nailed the problem, how do you solve it?
The reason for the color difference is that each color-capable device connected to your computer has its own special way of recording, displaying, or reproducing the same color values. The colors your eyes see may not match those that your scanner or digital camera can capture, nor will they perfectly match what your monitor or desktop printer can reproduce.
Will you ever be able to match the original scanned image exactly? Unfortunately, the answer is a qualified "no." What you can do, though, is to try to achieve a reasonably close display facsimile. CorelDRAW Graphics Suite 12 lets you do just that.
Color management enables you to match colors between devices that use color profiles - descriptions that conform to standards set out by the International Color Consortium (ICC). The profiles are compared according to the internal RGB color space shared by CorelDRAW 12 and Corel PHOTO-PAINT 12, and the corrections that are fed back to your monitor are based on each device's capabilities. When you print an image, your monitor's profile is compared with the printer profile, and your monitor's colors are corrected to reflect what the printer will actually print. If the colors aren't right, your monitor will tell you.
These days, color profiles are often readily available. Newer color devices automatically copy profiles to your system during installation. Others are supplied on disc by the device manufacturer. Often, you can install color profiles automatically through your operating system, using Plug and Play technology, or you can obtain them online. If you need a specific ICC profile, the best place to look is the support area of the manufacturer's Web site. Here are a few popular sources:
A Step-by-Step Approach for the Wary
The Color Management feature of CorelDRAW Graphics Suite 12 is much easier to use than in past versions, but it's still a full-featured tool. The main dialog serves two functions: it graphically illustrates the current color management setup, and it provides control over all options in a central location. You can access these options (shown below) from within either CorelDRAW 12 or Corel Photo-PAINT 12 by choosing Tools > Color Management.
Step 1: Assign Your Device Profiles
Choosing a profile to a color device is a simple step, provided that your hardware appears in the selector list. If you don't see it listed, you can load a profile from disc or connect to Corel's server, which provides a list of profiles to download (as shown below). If the profile for a connected device isn't available, leave the selection set to its generic profile (the default) until you can obtain one. Just remember that choosing the correct monitor profile is the most critical step in the process.
Turn color management on or off by clicking the arrows between the graphic icons for your color devices and your internal RGB color space. In the illustration below, each device is set to the active state. Turning the active state of a device off essentially disables its profile so that no color correction is applied. The arrow pointing to the Internal RGB profile from the Import/Export icon controls whether correction is applied to imported documents that have embedded ICC profiles. The arrow pointing in the opposite direction controls whether your current ICC profile is included with exported images - which is often the best route.
With your profiles assigned, you can choose which printer's capabilities your monitor will emulate by clicking the arrows that point from the printer icons to the monitor icon (shown below). Ideally, you'll choose the device that you will use to print the final result. Clicking either of the arrows automatically activates that printer's color profile. Only one printer's capabilities can be simulated at a time, so activating one printer's color profile turns off the other printer's color profile.
Step 4: Save Your Settings
After you've gone through the effort of assigning profiles and setting preferences, it's worthwhile to save your setup using the color management Styles options. To save the entire arrangement, click the "+" button, and name your new style in the Save Color Management Style dialog (shown below).
Tackling More Advanced Options Besides being able to set profiles and choose correction preferences, you can also use the Color Management dialog to choose more advanced settings for certain devices and operations. These settings are perhaps the most complex and critical of all the options you need to choose. To access them from the Color Management dialog, click directly on a specific graphic icon (Import/Export, Printer, Monitor, or Internal RGB). In the dialog that opens, you can set the following advanced options.
Advanced Import/Export Settings. Clicking directly on the Import/Export icon opens the dialog shown below. Here, you can specify whether you want to use the embedded ICC profiles contained in imported images, or whether your current profile is embedded into images you're exporting from your document. In either case, you can override the profiles converted or embedded by choosing to use your current Internal RGB profile or the profile for a specific device.
Advanced Internal RGB Settings. Clicking the Internal RGB icon opens a settings dialog that lets you choose from a collection of rendering intent types (shown below). This dialog also lets you change color engines from the default Kodak Digital Science color-management module if an alternate is available. The rendering intent method you choose controls how your internal color space converts and displays out-of-gamut colors on your monitor.
- Absolute Colorimetric. This method is useful if the gamut of the color proofing printer you're using is larger than the gamut of the final output printer you're attempting to simulate. It essentially preserves all in-gamut color, including the white point, which affects image highlights and contrast. This method maps out-of-gamut colors to the next closest hue by altering their saturation and lightness when displayed.
- Relative Colorimetric. If your drawing consists mostly of color vector objects, you might prefer this method. It's similar to the Absolute Colorimetric method, but it also alters the white point of the image, which can potentially change highlights and contrast. If you're proofing to an inkjet printer, this method is your best bet for displaying an accurate screen image.
- Perceptual. You might prefer this method for documents with vivid color, such as scanned photographs or digital camera captures. The Perceptual method compresses a larger gamut of colors to fit a smaller one by desaturating all colors.
- Saturation. This less complex method maps colors between devices directly, regardless of the differences in lightness, saturation, or hue. It's suitable if only solid colors are involved and if color accuracy and consistency are not required.
- Automatic. This method is the default and perhaps the best choice for general use. With Automatic selected, vector object colors are mapped with the Saturation method, and bitmap colors are mapped with the Perceptual method.
Steve Bain is an award-winning illustrator and designer, and the author of nearly a dozen books, including CorelDRAW 12: The Official Guide