The built in render of Studio, 3Delight, is equivalent to Firefly. Many users have started using LuxRender via my plugin, Reality. This option gives you freedom of choice at a very reasonable cost. The materials are defined in the Surface tab, specifically you want to look at the Advanced section of that tab, where you find all the settings for the Shader. If you need more control you can then look at the Shader Mixer in the tools menu, for a nodal system. If you use Reality then the plugin own's interface has the definition of the physically-based properties for Lux's Shader. Good luck.

Paolo

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