Analysis of original image: This image has two obvious problems. First, it lacks contrast and detail because it does not have a full tonal range. A correction is required to improve sharpness and detail in areas such as the shirt and the man's hair. Second, the image has a strong yellow-green cast. This leads in particular to a very unnatural skin tone.

Step 1 of this correction is an adjustment to the Contrast slider in the Controls tab of the HSL group. This adjustment (which sets the Contrast slider value to 11) illustrates one of the simplest ways to affect the tonal range of an image. Despite its simplicity, the correction improves the image noticeably. Compare the look of the man's hair on either side of the split-screen dividing line.

Step 2 of this correction eliminates the color cast by making a single adjustment on the Midtones ChromaWheel control on the Hue Offsets tab of the HSL group. Since the image is obviously too green, the correction is made by moving the crosshair pointer away from green. The adjustment shown is Hue:–94, Amount:11. (This places the crosshair between the magenta and blue parts of the wheel, opposite a point between green and yellow. The sample RGB values below confirm that we are reducing both yellow and green in the image.) This successfully restores a good skin tone and reveals the man's shirt to be blue.

Sample RGB values: A sampling of an area of the man's shirt before and after the corrections shows the following values:

These numbers reinforce the nature of the corrections that have been made. The hue offset adjustment has reduced the red and green levels significantly while preserving the amount of blue in the image.

Alternative techniques: Several alternatives are available for making the tonal range adjustments to this image. You could use the Gain, Gamma, and Setup sliders as an alternative to the basic adjustment on the Contrast slider. Another alternative for making the contrast adjustment would be to use the Master ChromaCurve graph in the Curvesátab.