@Chris Murphy LED lights and fluorescent lights do not emit a nice black-body gauss-shaped spectrum, they emit all their energy on a few narrow lines in the spectrum.
β² @clacke@libranet.de: In case it's unclear what I'm talking about, sunlight or a good old lightbulb has a light spectrum that looks like this:
111111122221111111111111111
But an LED light has a light spectrum that looks like this:
000090000000090000000090000
A fluorescent light is not RGB, but it is also made of spikes rather than an even curve, the spikes are just just placed in other places. So you could have a shirt that has three different colors when you view it in white light, LED light and some common configuration of fluorescent light.