[Theodoric]

From a book on Photoshop Elements 2 that I've currently on loan from our library (without pictures, I'm afraid).

Calibrating Your Monitor and Building an ICC Profile

Here I'll show you how to use Adobe Gamma, a utility that comes with Photoshop Elements, to calibrate your monitor. Before you begin, you should know several things about the response and performance of your monitor, including the manufacturer-suggested color temperature, gamma, and phosphor settings. Color temperature reflects the monitor display color for the white point, which really measures the color of white on your monitor. It is usually 5000, 6500, 7500, or 9300 degrees on the Kelvin scale. It is a characteristic of your display and can subtly affect the appearance of color on screen.

Gamma is a measure of tonal response, often a number with two decimal places between 1 and 3. Phosphors are a set of six numbers with x and y coordinates for red, green, and blue; these numbers can be up to three decimal places. These settings vary between monitor brands and models, so don't make assumptions about them or copy someone else's. Find the settings in your manual or contact the manufacturer (via the website or technical support).

Monitor manufacturers don't always put monitor specs for phosphors, white point, and gamma in the manuals. When you obtain the information, write it down. I usually write the | settings right on the cover of the monitor manual for easy reference.

Your monitor should be in an area that will minimize glare, and lighting (except where noted during the calibration) should be as you will have it when you are most frequently using the computer and monitor. Lighting should generally be subdued and indirect if possible. Changes in lighting will require recalibrating the monitor. The monitor can be calibrated to different light conditions, but it is easier to maintain a consistent room lighting than to add it as a variable in color corrections. Extremely bright or overly dark rooms might cause some problems with calibrations and monitor viewing. Optimally, room lighting should be bright enough that you can read and view materials that are not on the screen, yet not so bright that it causes glare or washes out the display. After creating your profile, be sure the lighting where you work remains the same as when you calibrated the monitor.

Before you begin, you should also locate the monitor's brightness, contrast, and color controls. If your monitor has an option to reset to factory settings, do it now.

1. Turn on your monitor and system, and let the monitor warm up for at least 30 minutes.
Calibration will be slightly different in every operating system and OS version, though the screens will be similar. For example, in Mac OS X, you should use the Display Calibration Assistant. I'll walk you through the Mac OS 9 version, and you can adapt this to your computer.

2. If you haven't done it yet, read the owner's manual for the monitor to see if it provides suggestions fcr calibration.

3. Open Adobe Gamma by double-clicking the iccn in the Control Panel folder. You should see the screen illustrated in Figure 1.7. If Adobe Gamma is not in the Control Panel folder, find it on the Photoshop Elements CD.

4. Click Step By Step. This will lead you through the process of calibrating and creating an ICC profile for your monitor. Click the Next button.

5. In the Description field, type a name for the pnfile you will be creating (Figure 1.8). You can enter a lot of information here, but it's best to keep it short. I find it handy to name the monitor and add the date, so the profles are easy to identify. If you use output white point settings (Step 12), you may also want to include this value in the name. Click the Next button.

6. Using the monitor controls, set the contrast all the way up and then adjust brightness until the smaller gray box in the center is dark enough that it is just barely discernable from the larger black box surrounding it (see Figure 1.9). If you notice the white frame beginning to darken at any point, stop darkening the screen. If necessary, adjust the brightness lighter a bit until the frame is bright white again. As you fine-tune this adjustment, it may help to squint or use your peripheral vision to get the center square as dark as possible without losing the brightness of the white frame. When you are satisfied with the adjustments, click the Next button.

7. On the screen that appears, select Custom to open the Custom Phosphors screen shown in Figure 1.10.

8. Type the six values obtained from the manufacturer of your monitor in the appropriate fields. You don't really have to know what each number means, but you do have to place each one correctly. Click the OK button to close the Custom Phosphors screen and accept the changes. This returns you to the Adobe Gamma Assistant dialog box.

9. Click the Next button. The screen that appears (Figure 1.11) allows you to adjust gamma. Check the View Single Gamma Only check box. Using the slider, adjust the appearance of the outer square (the alternating lines of black and white) so that it matches the tone of the 50% black center. Adjust the appearance by squinting at the screen (to blur the box slightly in your vision) while moving the slider. The goal is for the entire square to seem to have a uniform tone.

If you change monitors, you will obviously have to build a new profile. Other less-obvious reasons to build a new profile are: monitor aging and changes in response due to use, replacing your system hard drive, and changing room lighting (or computer placement).

10. In the Gamma field, type the Gamma value you got from the manufacturer. You will be able to enter a two-decimal value, but Adobe Gamma will round the value off when you save the entry.

11. Click the Next button. The screen that appears (shown in Figure 1.12) allows adjustment of the monitor's white point. Set the monitor's white point by choosing the value in the drop-down list that corresponds with the number you got from the manufacturer. (If you do not know what value to choose, see the following note.)

A second option on this screen allows you to measure the white point. To do this, dim (or turn off) the lighting in your work area and click the Measure button. A set of three gray squares will appear on a black background. Click the square that seems most flatly gray and repeat until the test closes.

12. Click the Next button. The screen that appears (Figure 1.13) will allow you to select a white point for output. This selection should be based on the color temperature of the intended output media. If you are unsure, or you are creating images for the Web, use the Same As Hardware setting.

13. Click the Next button. The next screen (Figure 1.14) allows you to compare calibration before and after the adjustments you made in the previous steps. Click to toggle the Before and After buttons several times, comparing the appearance of your screen as you toggle back and forth. Specifically, note the grays in the dialog box and see whether the color appears more neutral before or after adjustment. The more neutral (lacking any color, and looking flat gray), the better the calibration.

14. If the before and after results are noticeably different, run through the process again (Steps 3 to 13).

15. Click the Finish button to accept the changes.

I never calibrate one time and sit back satisfiedâ₠¬â€even when using a calibration device. 1 run through the process a few times.

What you have just done is calibrated your monitor and created an ICC profile for it. The calibration helps you to be sure the image information you see on screen is reasonably accurate. The ICC profile is a description of your color space and other data that helps describe how color appears on your system. This information can be used if you embed profiles in your images, to help describe color in your image to other ICC-aware devices.

Although Adobe Gamma is an adequate tool for visual calibration, calibration devices (see the example in Figure 1.15) can measure more accurately than your eye, and will probably measure a greater number of gray levels and create more accurate profiling. The devices take measurements directly from your screen, and create a profile based on those measurements. Using such a device can ensure that your monitor is calibrated properly, and it may actually save some time during calibrations.