Color Correction and Restoration - Beginning Photo Retouching and Restoration Using GIMP - page 86

6. The effect makes the image look much better, but I found the initial result a little

too strong, so lowering the layer's opacity to 90% did the trick. The contrast could
be bumped up a bit, so at this point, duplicate the background layer and merge
the Color Correction layer down (Figure 4-11 ).

Figure 4-11. Lowering the layer's opacity a bit, to reduce the effect

7. Open the Curves dialog box (Image Menu ➤ Colors ➤ Curves). Make a slight

S curve, as shown in Figure 4-12 (we just want to bump the contrast up slightly).

Figure 4-12. A slight S curve will bump up the contrast

The end result looks much better (Figure 4-13 ). Slightly increasing the contrast makes the man's
undershirt less conspicuous under the thin fabric of the pale yellow shirt. Use the Color Picker tool to
sample the wall again. You'll see the percentage of red is now closer to that of the green and blue, resulting
in an almost perfectly neutral gray. The Hue Variations function is often all that's needed to correct a color
cast—perhaps not in every case, but it's a good place to start.