In this shot two of my acting/dance students are doing a bit of Bob Fosse choreography where they swing there arms back and forth. They are wearing rave gloves that slowly change colors so we get a rainbow effect as the long exposure tracks the choreography through time. This choreography was done during a 15 second exposure.
This shot was taken in a studio at the University of Connecticut, and there were 7 of us working together in the room to make sure it was dark enough, the choreography was right, the angle of taking the picture was right, etc.