Apple Shake 4 - Manual (Page 454)

454 Chapter 16 Compositing With Layer Nodes
AddMix Example
In the following node tree, a key is pulled from the foreground using a KeyLight node.
The foreground is then attached to the background tree. The first “Closeup” illustration
(on the left) shows the default result, a result identical to an Over node. Ringing
problems occur along the hair (a bright ring), and along the shoulder (a dark ring).
When the curves are adjusted, the ringing is dramatically reduced, resulting in a much
cleaner composite.
Node tree Over1
Bluescreen AddMix1
Closeup, default curves Closeup, modified curves