Plastic is a nice example of a material with two different BSDFs mixed together.
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- You can lower the Refl 90° color, and/ or lower the Nd of the second BSDF to make it less shiny. Conversely, you can raise the Nd to make the plastic shinier, given that the Refl 90º is already set to the maximum value.
- You can increase the blending weight of the second BSDF so it will have more influence on the final look of the material.
The basic structure of a plastic material. You can download this sample material here.
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Avoid having more than one layer set to a weight of 100 in Additive mode. A material with three layers, two of which are set to Additive and have a weight of 100, will look unrealistically reflective. And it will also add to the render time. This does not apply to layers in Normal mode.
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