Coral PRR Instrument (IMAGE) Bermuda Institute of Ocean Sciences Caption For the study, a profiling reflectance radiometer (PRR) was deployed over the side of a boat in Hawaii and Bermuda. The instrument simultaneously measures the spectrum (intensity for each color of the rainbow) of light in the water column coming down from the surface, as well as the spectrum of light reflected up from the bottom. Credit Eric Hochberg, BIOS Usage Restrictions creative commons with credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.