Diffuse channel and Fresnel falloff

This tutorial shows how to use the material system to make diffuse surfaces react a bit more naturally to light. Diffuse surface scatter light uniformly. However in reality light tends to have a slightly less uniform behavior and this tutorial shows how to simulate that.
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Nuanced Metals II

Here is a tutorial on how to improve the realism of metals (and other similar materials). Compare the left and right images. Which looks more real? The right you probably say and would be right. The way light reflects off the surface is more correct. This tutorial explains how to achieve this.
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