This video tracks Michael Lesser from the surface down to the first of the many deep dives (150 feet deep on air). Michael is searching for novel types of fluorescence in corals and other marine organisms. During daylight is often difficult to see fluorescence but using specialized light (high intensity discharge [HID] light with a blue filter) and filter (yellow filter) you can clearly see cup coral fluorescence at depth. Video courtesy of of the Twilight Zone Expedition Team 2007, NOAA-OE.