Blender incorporates a rendering in volumetric Cycles that allows imaging increasingly realistic. Although the shader is in constant development, the degree of maturity that has largely simulates the behavior of light in different areas.
Together with the technical means to simulate participants as is the Scattering, the absorption of light along the volume of the scene allows us to play with its attenuation with distance from the emission source.
A new node with which continue to experience in our classes.
I leave an exercise in rendering as Wallpaper in HD TV (1920 x 1080) clicking with the mouse over the center image.