The Olympiastadion was equipped with the latest technology in artificial illumination and sound equipment.

In this age before widespread artificial illumination, these were used to tell the time after dark.

Inside, the shades had been pulled, and there was no artificial illumination.

The light from the registration desk was the only artificial illumination in the atrium.

This feature was used before artificial illumination to tell what time it was at night.

Dark blue also proved effective under artificial illumination during night actions.

They originated before widespread artificial illumination, to allow the time to be determined in the dark, and were also used by the visually impaired.

Colors were vivid without any artificial illumination, even at depths of 80 feet.

Similarly, it has long been known that hens lay more eggs if they are kept under artificial illumination.

This marks the end of the evening civil twilight, the point where artificial illumination is required to read outside.