Apple Shake 4 Tutorials - Manual (Page 105)

Chapter 3 Depth Compositing 105
This is an extreme color change, but it helps illustrate the issue with premultiplied
images. Time to tone it down a bit.
5 Load the Add1 parameters (click the right side of the node), then set the RGB color
values to 0.2, 0.11, and 0.07.
That’s a little better, but the blacks could use more contrast.
6 Select the Add1 node and insert a Color–ContrastLum node.
7 In the ContrastLum1 parameters, drag the value slider to 1.1, then drag the center slider
to 1.
This color correction works well for most of the balloons. One exception is the zeppelin
on the far right, which is too bright for the rest of the composite.
You can use a rotoshape mask to limit color correction for the small zeppelin.