Adobe Photoshop CS5 One-on-One

5. Decrease the Green values. The image appears decidedly green,
   so click in the numerical value field next to the Magenta-Green
   slider and enter a value of –10. This moves the Magenta-Green
   slider to the right, away from green. The results are depicted
   in Figure 6-11. The image has a lot of green objects, so it’s hard
   to tell exactly where to stop in your attempt to remove the green-
   based cast. But since the overall goal is to cool down the image,
   we need to be judicious about contributing too much magenta,
   so best to be conservative here.

Figure 6-11.

Figure 6-12.

6. Increase the Blue values. The image is still too warm for my
   taste, so cool it way down by moving the third slider all the
   way to +40, thus increasing the blue value. You’ll notice in
   Figure 6-12 that the wall behind the boys and the sofa color
   are at last approaching a neutral gray.

Before green adjustment

Before blue adjustmentAfter adjusting to +40 blue

After adjusting to –10 green

186 Lesson 6: Adjusting Color and Luminance