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This powerful feature lets you then composite lighting elements in comp or mix them using 3Delight Display.
An example of how this feature can be used is detailed in Multi-Light Rendering.
Selecting
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Rigs and Lights Image Layers
The light sources and rigs defined by upstream GafferThree nodes are listed in the Multi-Light section. All light sources that are in a rig will be rendered in a single multi-light image layer. Enabling the Display All Lights option will add every light contained in rigs under the Lights section of the multi-light list. It then becomes possible to generate independent multi-light image layers for some or all of the lights that are in a rig.
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