Adobe Photoshop CS5 One-on-One

Figure 6-24.

The Adjustments panel switches to show the Levels Adjust-

ments option (shown in Figure 6-24).

6. Change the Adjustments panel to expanded view. It will be
   easier to work with the Levels adjustment command if you take
   advantage of an option provided in the Adjustments panel flyout
   menu. Click the at the upper-right corner of the panel and
   choose the first option, Expanded View. This gives you better
   visual access to the following options:
   
   
   • The Channel pop-up menu lets you edit the contents of
     each color channel independently. The default RGB setting
     lets you edit all channels at once. (Read the sidebar “The
     Nature of Channels,” on page 196, if you haven’t already.)
   
   
   • The black blob in the middle is the histogram, which is a
     graph of the brightness values in your image. (See another
     sidebar, “How to Read and Respond to a Histogram,” on
     page 200.)
   
   
   • The three Input Levels values list the amount of adjust-
     ment applied to the shadows, midtones, and highlights.
     The default values—0, 1.00, and 255, respectively—indi-
     cate no change.
   
   
   • The Output Levels values let you lighten the darkest color
     and darken the lightest one, thus reducing the contrast.
     Although useful for dimming and fading, they rarely come
     into play when correcting an image.
   
   
   • The Levels preset pop-up menu (at top) lets you apply
     a predefined collection of settings or save your own.
   
   
   • The Auto button applies the equivalent of the Auto Tone
     command, which you can modify as needed.
   
   
   • See the three eyedropper tools alongside the histogram?
     You can select an eyedropper and then click in the image
     window to modify the clicked color. The black eyedrop-
     per makes the clicked color black; the white one makes it
     white; the gray one robs it of color, leaving it a shade of gray.
   
   
   
   

PeaRl Of WISDOm

If you used the menu command rather than an adjustment layer, you’ll have
a Preview check box inside the dialog box that you can turn on and off to
see your before and after effects. Since we’re demonstrating the adjustment
layer approach here, you can “preview” the effects by clicking the for the
Contrast and Color layer in the Layers panel to turn on and off its visibility.

Adjusting Brightness Levels 199