218 ABSOLUTE BEGINNER’S GUIDE TODIGITAL PHOTOGRAPHY
FIGURE 14.16
Adjust the mid-
tones as the fin-
ishing touch,
and now the
underexposed
image is cor-
rected.The Absolute Minimum
A few point regarding histograms and adjusting brightness and contrast in images:
■ Histograms show the distribution of pixels in an image across 256 brightness
values. Pure black is on the left; pure white is on the right.
■ Use histograms to see whether your image is lacking brightness and contrast.
Empty, blank areas in the histogram indicate missing values.
■ Use the black and white sliders in the Levels dialog box to adjust brightness
and contrast.
■ Double-click on the black-point and white-point eyedroppers in the Levels
dialog box to set baseline black and white values.