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Learn to create mist in Blender with Cycles for environments

http://cgcookie.com/blender/2013/03/11/creating-mist-blender-cycles-z-depth/

When you’re creating expanse environments that are believable, one of the things you need take into account is the saturation of far away objects. As things get farther and farther away, they appear less saturated, almost like they’re covered in a slight mist. In order to create believable CG this is a very important detail to consider, particularly when creating your environments, as it greatly adds to the realism of your scene.

In this tutorial I’ll show you how to create an accurate, anti-aliased Z-pass with Cycles that can then be used to create this mist-like effect. This is done by creating a custom shader that makes use of the View Distance option of the Camera Data node for Cycles shaders.

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