Color Correction and Restoration - Beginning Photo Retouching and Restoration Using GIMP - page 92

3. Open the Levels dialog box (Image Menu ➤ Colors ➤ Levels). Because each

color channel has a different tonal value, we're going to make adjustments
on each one, to revive both contrast and color. In the Channels option, select
the Red color channel (Figure 4-21 ). Move the black point slider to the right,
stopping where the image data begins. Move the white point slider to the left,
stopping where the image data starts. (Wait until you adjust all three color
channels before clicking OK.)

Figure 4-21. Adjusting the levels in the Red channel

4. Select the Green color channel and repeat the same steps with the black and

white point sliders (Figure 4-22 ) as previously.

Figure 4-22. Adjusting the levels in the Green channel