Effect:
1. Open the original image material and click on the channel panel. You can see that the red channel has less damage and the green and blue channels have more texture.
We can use the Channel Mixer adjustment layer to highlight the good channels and hide the bad ones.
2. Add a Channel Mixer adjustment layer and change the layer blending mode to "Lighten". This helps brighten dark colors.
Instead of using the red channel, use the green channel as the source, and input green into the red channel. This will reduce the red in the original image, because the mixture of red and green produces yellow. So you see the red decreases and the yellow increases.
3. Select the blue channel as the source, and increase the blue appropriately to reduce the yellow. Because the opposite of blue is yellow, increasing the blue will reduce the yellow, and vice versa.
4. Compare the effects before and after the adjustment. After adjusting the channel mixer, the tone has been significantly improved.
5. Add a Hue/Saturation adjustment layer and reduce the saturation appropriately.
