Adobe Photoshop CS4 - Manual (Page 188)

181 USING PHOTOSHOP CS4
Color and tonal adjustments
Last updated 1/10/2010
With a low-key image, you may want to set the highlight to a lower value to avoid too much contrast. Experiment
with Brightness values from 96 through 80.
The pixel values are adjusted throughout the image proportionately to the new highlight values. Any pixels lighter than
the area you clicked are clipped (adjusted to level 255, pure white). The Info panel shows the values both before and
after the color adjustment.
Setting the target value for the Set White Point Eyedropper tool and then clicking a highlight to assign it the target value
5 To assign shadow values to the darkest area of the image that you want preserved, double-click the Set Black Point
Eyedropper tool
in the Adjustments panel to display the Color Picker. Enter the values you want to assign to
the darkest area in the image, and click OK. Then click the shadow you identified in step 3.
When you’re printing on white paper, you can usually achieve a good shadow in an average-key image using CMYK
values of 65, 53, 51, and 95. An approximate RGB equivalent is 10, 10, 10, and an approximate grayscale equivalent is
a 96% dot. You can approximate these values quickly by entering 4 in the Brightness (B) box under the HSB area of
the Color Picker.
With a high-key image, you may want to set the shadow to a higher value to maintain detail in the highlights.
Experiment with Brightness values from 4 through
20.
Matching, replacing, and mixing colors
Match the color in different images
The Match Color command matches colors between multiple images, between multiple layers, or between multiple
selections. It also lets you adjust the colors in an image by changing the luminance, changing the color range, and
neutralizing a color cast. The Match Color command works only in RGB mode.
When you use the Match Color command, the pointer becomes the Eyedropper tool. Use the Eyedropper tool while
adjusting the image to view the color pixel values in the Info panel. This panel gives you feedback about changes in
color values as you use the Match Color command. See “ View color values in an image ” on page 157.
The Match Color command matches the colors in one image (the source image) with colors in another image (the
target image). Match Color is useful when you’re trying to make the colors in different photos consistent, or when
certain colors (such as skin tones) in one image must match the colors in another image.