A special light is available to simulate the effect of sunlight or moonlight. It can be used in conjunction with sky simulation to provide a dramatic background and show how the shadows cast by a structure affect the surrounding area.
A "Sun" light is rendered using an accurate sunlight model. For example, the color of sunlight is computed based on the time, position in the sky, date, and location specified in the drawing. More properties become available with photometric lighting than in the standard lighting workflow.
The rays of the simulated sunlight are parallel and have the same intensity at any distance. The angle of the light from the sun is controlled by the geographic location you specify for your model and by the date and time of day. Whereas the rays of the sun are parallel and of a yellowish hue, the light cast from the atmosphere comes from all directions and is distinctly bluish in color. All settings for the sun except geographic location are saved per viewport, not per drawing. Geographic location is saved per drawing.
The simulated "Sky" background is only available with the photometric lighting workflow.
Sky illumination can be used to add extra light to a scene, simulating the effect of light scattered by the atmosphere throughout the scene.