Blur a mesh without nodes or cycles? I'm creating an Earth and it looks amazing! But the atmosphere still has sharp edges. I've created the glow but have had to make a transparent sphere around the earth to create another effect to symbolize distance. However, although this looks brilliant, I want the outer edges of the atmosphere/sphere to be blurred or feathered slightly. I don't know how to do this. I've tried in the compositor and shader, plus I don't want to use cycles as it will ruin all my current settings. Is there any way to blur a specific mesh/material in the shader, compositor or material panels without it effecting the nodes for everything else?

Here's a rendered image to help you out. From a different angle it looks great but it's just the atmosphere that ruins this angle:


Also, does anyone know how to darken the blue land of the night light map? It's very unrealistic to be seeing the land at night but I can't remember how I did it last time. Thanks in advance!!
This does not answer your question directly, but consider this as an alternatively way to implement a more realistic atmosphere effect. (With Blender Render)

Basically, you want to use the volume material type on a sphere, this gives you much more control over the density of the atmosphere, and you can tweak the density and colour without fussing around with blurring or nodes.

The following screenshot has all the settings you need to generate the atmosphere.



Blend File