Simulating the atmosphere Some months ago I watched this video of Blenderguru about "How to create a realistic earth in blender". In this video blender render is used and now that I understand texturing in cycles a little better I am trying to rebuild this "realistic earth" with cycles.



At about 22:00 min Blenderguru starts explaining how to simulate the atmosphere using blender render. The idea is that near the edges the atmosphere gives a bluish tint to the earth. I tried to work this out with the setup as above (same idea as used for a transparent balloon) but blender guru is doing something with fresnel. I think that is a better solution ? How to simulate the atmosphere with fresnel ?
I think what you want to do is mix whatever shader you are using for the earth's surface with a bluish shader towards the edges.



To do this just plug both shaders into a mix shader (like you already have), with the bluish atmosphere in the bottom socket.  Then control the mix factor with a Fresnel node.

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