It fascinates how light in a club blends and separates. I first noticed it here ( http://sinah.org/2009/11/26 )

I wonder if it is a digital photography thing, that is to say, the lens is not fast enough to capture the combined light or technically it doesn't know how to make sense of the colours.

If my drunk memory serves me well, we don't see the separate colours, so our eyes could be the problem too.

I think it's the lights. As in the kind of lights they use and how they are able to control their direction...just guessing