What’s happened to the waterfall? Why is it green?
The answer is rather subtle and ingenious. Sean Lenz and Kristoffer Abildgaard dropped high-powered Cyalume glow sticks in a variety of colours into various waterfalls, and captured the results using long exposure photography (varying from 30 seconds to 7 minutes). The final product is a stream of colour that is eerily beautiful and alien. More images can be found over at Colossal.