PxrAovLight is a handy utility light that allows a lighting artist to output a shot-specific AOV mask without needing to request one from the shading artists. In this example, we'll see a common request...getting a refraction AOV for a character's eye. In this case we'll simplify it with a red sphere inside a glass sphere.

Light Linking with PxrAovLight

Use light linking to include/exclude pieces of geometry in the AOV. In this example, the PxrAovLight is "off" globally and "on" for the eye in the scene.  This linking setup creates a mask of the eye ( red sphere )inside the refractive glass. 

Defining the Output AOV

Once you set an AOV Name in the PxrAOVLight attributes, use the Render Settings AOVs tab to define a new display to which PxrAovLight will write.

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