Underwater imaging has been used in applications ranging from marine science to downed-vessel location. Typically, objects of interest reside below the photic zone (300 feet), where surface light does not penetrate. Light sources can be either spectrally filtered or strobed to penetrate various water conditions. Ideally, cameras for underwater investigation are capable of low-light imaging and are engineered to fit into small packages mounted on either manned or remote vessels capable of extreme depths.
The image of a downed navy helicopter was viewed using a camera engineered for Primary Point Digitization™ (PPD). The CCD analog signal was digitized at the camera head so that the digital signal could be transmitted topside in an efficient manner. Image courtesy of the Marquest Group.