If you look at the sun parameters in the animation motion lab, you'll see independent timelines for color, sun disk color and intensity. How do I set the sun disk color? The only evident control works the same, both in the Sky&fog and in the Skylab: it changes only the sunlight color, but the only timeline that changes is sundisk not color. In the motion lab there are other undocumented timelines, like sun rotation and shear.