The leaves will turn bronze or even almost red under high light levels.
This is a natural response to lower light levels and confined air quality.
Many can automatically adjust to give you the right light level, every time.
They must get bright light levels throughout the year to flower well.
Night vision systems get screwed up by the light levels.
"We saw a nice increase in light levels," he said.
There were no windows and the light level had dropped by more than half.
The light levels used here would certainly be much lower than this.
It's most likely to occur when light levels are low.
Often the primary goal is to control not temperature but light levels.