Apple Shake 4 - Manual (Page 427)

Chapter 15 Image Processing Basics 427
To create the same error here, continue with the previous node tree and do
the following:
1 In the Node View, select the IMult1 node, then click Color–Add.
An Add node is inserted into the tree, between the IMult1 node and the IAdd1 node.
2 In the Add node parameters (click the right side of the node to load its parameters into
the Parameters tab), set Color to .5.
The same error occurs—the entire image brightens, not just Munch. This is not what
we want to happen.
For a clue, you can double-click the Add (Add2) node. There is no longer an exact
correlation between the black areas of munch_mask and the black areas of the RGB
channels.
Add2 munch_mask