Add a matte to the Matte pipe of the CBlend and MBlend nodes to limit the area on the image where the colour correction or matte will be applied.

You can use any matte operation in the Matte pipe—add any combination of nodes that you would want to use to isolate an area of the front image. For example, you could add a garbage mask node to the Matte pipe of the CBlend node.

To add a matte to a blend node:

1. Select Move mode, and then select the node in the bar.

   
   

2. Drag the node to the Matte pipe. Release the cursor.

   The node is added to the Matte pipe.

   
   

   Image courtesy Behavior Communications Inc.

3. Use the node menu to create the matte.
4. Add other nodes you want to use to refine the matte.