Visual QuickStart Guide [Electronic resources] : Mac OS X 10.4 Tiger

Maria Langer

نسخه متنی -صفحه : 300/ 257

DigitalColor Meter

The DigitalColor Meter (Figure 30 ) enables you to measure colors that appear on your display as RGB, CIE, or Tristimulus values. This enables you to precisely record or duplicate colors that appear onscreen.

Tip

A discussion of color technology is far beyond the scope of this book. To learn more about how your Mac can work with colors, visit the ColorSync page on Apple's Web site, www.apple.com/colorsync/.

To measure color values

Open the DigitalColor Meter icon in the Utilities folder (Figure 1 ) to display the DigitalColor Meter window (Figure 33 ).

Figure 33. The DigitalColor Meter can tell you the color of any area onscreenin this case, one of the pixels in its icon.

Point to the color onscreen that you want to measure. Its values appear in the right side of the DigitalColor Meter window (Figure 33 ).

If desired, choose a different option from the pop-up menu above the measurements (Figure 34 ). The value display changes to convert values to that measuring system (Figure 35 ).

Figure 34. Choose an option to determine the system or units of the color measurement.

Figure 35. Choosing a different color measurement option from the pop-up menu changes the way the color values appear.

Tips

You can use commands under the Image menu (Figure 36 ) to work with the color sample image that appears in Digital-Color Meter's window:

Lock Position () prevents the image from moving.

Lock X () allows only vertical changes in the color sample.

Lock Y () allows only horizontal change in the color sample area.

Copy Image () copies the color sample image to the clipboard.

Save as TIFF () saves the color sample image as a TIFF file.

Figure 36. Use the Image menu to work with the sample image.

You can use commands under the Color menu (Figure 37 ) to work with a selected color. (For best results, either use the command's shortcut key or choose Image > Lock Position [

Figure 36 ] before using the Color menu's commands.)

Hold Color () saves the color in the sample well until you choose the Hold Color command again.

Copy Color As Text () copies the color information to the clipboard, where it can be pasted into other applications.

Copy Color As Image () copies the color information as a color sample to the clipboard, where it can be pasted into other applications.

Figure 37. Use the Color menu to work with sampled colors.

You can change the amount of color that is sampled by dragging the Aperture Size slider to the right or left (Figure 38 ). A large aperture size will average the colors within it.