OFOBS Seafloor images from the margins of the Atacama Trench, collected during RV SONNE cruise SO261@en

The Ocean Floor Observation and Bathymetry System (OFOBS) was used during the SO261 cruise to the Atacama Trench, Chile, to image the seafloor at 4,000 - 6,000 m depth, on the eastern and western margins of the trench. The OFOBS system consisted of a towed underwater camera system equipped with both a high-resolution photo-camera (iSiTEC, CANON EOS 5D Mark III) and a high-definition video-camera (iSiTEC, Sony FCB-H11) as well as an intergrated sidescan sonar system. The cameras were mounted on a steel frame (140L x 92W x 135H cm), together with two strobe lights (iSiTEC UW-Blitz 250, TTL driven), three laser pointers spaced with a distance of 50 cm used to estimate the size of seafloor structures, four LED lights, and a USBL positioning system (Posidonia) to track the position of the OFOBS during deployments, with additional positioning information provided by the newly integrated INS and DVL systems. […]