Apple Shake 4 Tutorials - Manual (Page 170)

170 Chapter 5 Using Keylight
6 Connect the RotoShape node to the fourth input (GarbageMatte) of the Keylight node
to remove the gunk on the side of the image.
Now the rotoshape matte must be inverted.
7 In the Node View, select the RotoShape1 node.
8 Apply a Color–Invert node to the RotoShape node.
The mask is reversed.
9 Activate the VLUT2 button.
Hold down the button, then choose VLUT2 from the pop-up menu. You do not have to
modify the Viewer lookup values; they are saved for the session.
When VLUT2 is enabled, you’ll see an edge on the mask. You can soften this with a Blur
node.
10 Select the Invert1 node and insert a Filter–Blur node.