Math Composite
Description
Math Composite combines two clips using one of many Blend modes.
Note: You can change Math Composite’s input order with the User Interface > Trees > Input Order preference. By default, FG, BG is selected, but you can change it to BG, FG if you’d like.
Node Group
Composite.
Controls
Blend
Selects the Blend mode that is used to combine the foreground and background.
See the
Appendix G - Blend Modes chapter for a detailed list and description of available Blend modes.
Level
Sets the level of the foreground element.
Black Clip
Blacks are made blacker by increasing this value. As the value increases, more values are clipped to black.
Note: Often times the black portion of the image is not entirely black. This becomes an issue if something like fire is shot against a black background. If the black is not entirely black, then these impure black areas will be added to the background image as part of the Math Composite causing the final result to have “milky” blacks. The Black Clip parameter has been added to easily adjust the foreground image’s black level.
Channels
RGB, RGBA, Alpha, Red, Green, Blue
The Blend modes affect the selected channels.