Operation Manual

As you perform a tonal curve adjustment, a histogram is displayed behind the tonal curve
and is updated as you manipulate the tonal curve. You can specify the tonal range of the
histogram to focus the graph on the part of the tonal curve you plan to work with. For
example, if you plan to manipulate the contrast in the shadow areas of the image, you
can limit the tonal range of the tonal curve and histogram to display pure black to 50
percent gray only. You can also extend the range of the histogram and tonal curve beyond
pure white to capture highlight detail that would be clipped otherwise.
You can also adjust the tonal curve of each color channel independently. For more
information, see Using the Curves Controls for Color Correction.
Before Curves adjustment After Curves adjustment
To adjust the tonal curve of an image based on luminance
1 Select an image.
2 If the Curves controls are not shown in the Adjustments inspector or the Adjustments
pane of the Inspector HUD, choose Curves from the Adjustments pop-up menu.
Channel pop-up menu
Curves Action pop-up menu
543Chapter 17 Making Image Adjustments