Underwater imagery of the substrate and coral reef habitat on the Kona coast of the Island of Hawaiʻi, from 2003, 2004, and 2022

Information about the acquisition times and positions is recorded to the image metadata (EXIF) header for each image. The positions of the images were determined using boat-mounted GPS receivers. Because the images were acquired using cameras towed behind the boat, or lowered beneath the boat while drifting, the offset between the GPS receivers and the actual position of the camera is unknown. Thus, the positions recorded in the image metadata reflect the position of the boat during acquisition and not the actual position of the camera. For the images acquired during field activities A803HW, A204HW, and A604HW the GPS positions were acquired using an autonomous single-frequency GPS receiver, with positions embedded into video format, and exported during still-frame export. Some images from these field activities have the geographic positions and acquisition date and time (UTC) stamped onto the image. The geographic positions for these images are referenced to the WGS84 reference frame (EPSG:4326). For images acquired during field activity 2022-615-FA, the geographic positions were acquired using a dual-frequency GPS receiver, with positions post-processed using a nearby base station. The precise time of each image acquisition was recorded in a text file, and geographic positions for each image were interpolated from the continuous GPS trajectory. The geographic positions for these images are referenced to the NAD83(PA11) reference frame (EPSG:6322).