Old network
As of Houdini 20.5, use Copernicus nodes instead of Compositing nodes. Though both networks still exist, the Compositing network is now designated as COP Network - Old. The Compositing network and its nodes will be deprecated and then removed in a future Houdini release.
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Each node that takes a mask has options to let you quickly perform common modifications to the mask input: resize mask to fit image, invert mask, and masking amount.
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Use Follow display/current mode in the compositing viewer to use the manipulator from one node while viewing the effects on a downstream node.
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Learn about the options of the compositing viewer . Don’t forget you can use the timeline mode when editing timing nodes .
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Use the
thumbnail flag to show what a node is doing
without re-cooking.
Working with High Dynamic Range images ¶
High Dynamic Range (HDR) images provide much more flexibility for compositors by providing much more color information. However, they also cause some problems in compositing:
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Using color correction operations, you can easily create colors with negative or super-white components when doing normal color corrections. Negative color components can cause unexpected results when compositing over other images.
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Alpha can also be drawn outside the 0-1 range. This produces strange results when using compositing operations that depend on alpha to blend (over, inside, and XOR).
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HDR colors don’t work well with the screen compositing operation, which will cause some odd color shifts.
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Applying gamma to HDR images, especially low gamma, can cause super-whites to become extremely bright.
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LUTs have a limited range, usually black-white. Applying a such a LUT can cause unwanted clipping of HDR information
To reduce these problems:
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Use a limit COP to clamp HDR information where it is not needed.
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Use color curves for finer control over HDR ranges (Color Curve COP).
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Convert alpha to 16bit int.