Challenges in underwater image capture

Recent advances in digital electronics technology have made the collection of both still and video images cheaper and easier than ever before. These advances have allowed engineers to create more miniature low power image capture systems that can collect increasingly detailed imagery of deep sea organisms and habitats. As the technology has progressed, so has the demand for the use of such imaging systems for science. In the marine field, advanced imaging systems have provided scientists with unique perspectives into underwater habitats and marine life. Developing such systems for operation in marine environments at extreme depths, poses some unique engineering design challenges. The enormous pressures and low temperatures experienced at depth require systems to be enclosed in special housings which protect the equipment, but allow for crystal clear images to be collected. At depth, lighting must be used to illuminate otherwise dark habitats and biota. Choice of lighting is critical to achieve accurate color definition while minimizing backscatter and target wash out. In addition, the design of stereo systems requires special attention to camera registration, optics and frame synchronization. Support systems must also be developed to process and manage the large data streams being generated by modern image capture systems. This paper will discuss challenges with design of such systems, and outlines design approaches for selection of sensors, optics, housings, lighting, and the creation of stereo systems for size estimation of target data collected from both video and still imagery in the deep ocean.