Lighting demo by Godzilla

This thread by Godzilla shows the effect of enabling and disabling different channels of the sun + sky lighting model that comes built into Indigo.

The first image is with the full sun + sky lighting model:

The second image is with the sun disabled, but sky lighting (atmospheric dispersion) enabled:

And finally, with only the sun enabled, but sky lighting disabled. This is similair to the effect you get at night, where the light from the moon isn't bright enough to be scattered all around the atmosphere, but instead casts more direct shadows.