A high resolution electronic still camera with full ocean depth housing

Summary form only given. Since the first underwater images were made in the 1890s, there has been an interest in visiting, via photographs, the otherwise inaccessible depths of the oceans. Of the many types of imaging devices available today for taking pictures of the ocean floor, the film camera still provides the finest resolution over a wide dynamic range. Yet the requirement of retrieving the film and processing it into prints frustrates our desires to see instantly the results of a project. Video has to a large measure fulfilled the requirement to bring the ocean floor instantly to top side observers, and is used extensively in research and exploration. But for those who require a very wide dynamic range image with high spatial resolution, the new electronic still cameras are an excellent choice, and the time required to receive and view the image is only a few seconds. This paper describes an electronic still camera (ESC) developed for deep ocean imaging by Woods Hole Oceanographic and Princeton Instruments Inc. and in use on a deep towed sled operated by the Naval Oceanographic Office. The camera, with a 1 K by 1 K coded CCD, is packaged to fit into a 6 inch ID pressure housing and dome port assembly. It is completely self contained, requiring only power and a communications link to a surface data acquisition and display computer. Two systems have been operating successfully on many missions, and on the last cruise over 150000 images were continuously recorded during a single long mission. Images from the ESC are displayed in real time on a PC monitor and simultaneously recorded to DAT tape