Download the app to your computer
Availible for Mac and Windows
When the application opens, the time is set to noon. You can set the slider to different times of the day and see how the natural light decreases or increases.
Play around and see how a poorly installed illuminator lets the shadows cover the man in the shade or how brightness and glare makes the object invisible. And, if it's important to see colored details like the sign on the man's t-shirt, what type of light should you go for?