March 11, 2011, 6:24 a.m.
posted by lordnikon
Another way to recolor an image with gradient mapping is to use layers and blending modes. What you do is create a copy of the layer containing the image that you want to recolor, apply a gradient map to the copied layer, and then use a blending mode to blend the copied layer’s pixels with the original layer. Find an image and give this a try:
Open the image that you want to recolor.
I’m using my feathered vulture friend again. (He was last seen lurking in Figure.)
In the Layers palette, select the layer containing the image that you want to recolor.
Choose Layer>New>Layer via Copy.
A copy of the original layer appears in the Layers palette.
Select the copied layer in the Layers palette.
Choose Image>Adjustments>Gradient Map.
In the Gradient Map dialog box that appears (refer to Figure), use the Gradient picker to select a gradient.
Click OK to close the Gradient Map dialog box and apply the gradient to the copied layer.
In the Layers palette, use the Blending Mode drop-down list to select a blending mode.
For a first try, I suggest using Color mode. This blends the colors in the copied layer with the colors in the original layer. Experiment with the blending modes to see what kind of results you get. Some can be quite subtle, but others are downright bizarre. Check out the vulture’s recoloring in Figure. (He doesn’t look too happy about it!)
You can also apply a gradient map as an adjustment layer. To find out more about adjustment layers and how to use them, take a look at Technique 22.
To enhance the contrast between the colors added by the gradient mapped layer, insert a Posterize adjustment layer between the original layer and the copied layer. You can do this by selecting the original layer and then clicking the Create New Fill or Adjustment Layer button at the bottom of the Layers palette. Select Posterize from the menu and then set the number of levels to 4 or 5. (Turn to Technique 22 for more about adjustment layers.)