Sun and sky system

A sun and sky system creates two linked light sources in a render engine: the direct beam of the sun and the softer, scattered light of the sky dome. Lower the sun and everything shifts with it, from the color of the light to the length of the shadows and the tone of the sky. Noon gives a hard, almost white light. Late afternoon turns warm, with long shadows raking across the facade.

How it works

Most systems are driven by two values: the sun’s direction and its altitude. You can type them in or let the software work them out from a geographic location, a date and a time, which shows exactly which facade catches light at which hour. The sky model imitates scattering in the atmosphere, and settings such as turbidity or haze control how clear the air looks. Light from a low sun travels through more air, so it reddens near the horizon; a good sky model does this on its own.

Using it in architectural visualization

For exterior renders it is a quick, consistent starting point: natural daylight without hunting for an HDRI. It also helps with shadow studies, where the same camera is rendered at several times of day to see where shadows land on neighboring plots. Indoors, the sun throws crisp patches of light through the windows while the sky fills the room, and exposure has to balance the two. We explain how we set up exterior light in our exterior visualization guide.