Deep-sea underwater cameras may take either video or still images with high-resolution digital cameras. There are a huge range of underwater cameras for every purpose but they all have several things in common.
They all need a waterproof housing, such as a heavy metal tube or housing, to contain the camera or video device. They also need an underwater lighting system or flash strobe because the ocean depths are too dark to view without artificial light.
These items can be mounted on the frame of a benthic sled, which is towed behind a ship along the seafloor, often with a live feed to the surface for scientists to view the marine life. Other cameras can be mounted on remotely operated vehicles (ROVs) which are tethered to the ship, or on autonomous underwater vehicles (AUVs) which are actually robots with no tether.
High-resolution still images can be used to detect the shape and colour of even tiny sea creatures, or the video can be used to watch the behaviour of marine wildlife.
When towed over long distances, underwater cameras can tell scientists much about the detailed underwater landscape and how the marine communities are associated with the various seafloor habitats.
Of critical importance is the ability to apply a timestamp and navigation position to the still images or video. As the GPS position of a vessel is usually recorded onboard, in addition to GPS time, then any imagery which is also timestamped can be directly related to a position in the water.
The addition of an ultra-short baseline transducer to the underwater camera, can also provide a depth value together with the latitude and longitude. Therefore underwater cameras can be very accurately located in the water column and the viewed marine life or seabed habitats located on the seafloor.
The Gallery images and Movie below are examples from various underwater camera surveys conducted on the Great Barrier Reef, Coral Sea and in Antarctica. All underwater images were taken automatically by remotely operated vehicles (ROVs) or autonomous underwater vehicles (AUVs)