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Below you can find a step by step example of creating a patina on a bronze statue that is then composited into a plate. At the end of the page there's a file package for you to try!
Step 1: To begin you should assign a PxrLayerSurface material to your object. This tells RenderMan which materials will be rendered for the assigned object. Leave it at default unless you prefer a different specular model. This must be changed in the assigned PxrLayerSurface. GGX is chosen as the specular model for this example. In Maya we automatically create a base and upper layer.
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