Abstract
This study evaluated the relative performance of three cameras, an action camera (GoPro Hero 12 Black) and two DSLRs (Canon EOS Rebel SL3 18&24mm lenses) using three metrics; spatial accuracy, color accuracy, and image resolution. Test objects and a color/resolution chart were imaged across three days and different environmental conditions. Spatial accuracy was consistent among the three camera types with average percentage error ranging from 1.39% to 1.65% and actual error ranging from 0.0030 meters to 0.00035 meters, indicating reliable measurements underwater regardless of camera type. Color accuracy showed a much wider range of error/differences with all cameras struggling to produce accurate red, green, and blue color values underwater compared to the actual or on-land values, due to color attenuation. Resolution measurements showed a divide in the cameras, with the 24mm lens Canon camera exhibiting the sharpest resolution values and the GoPro cameras having the lowest resolution values. Overall, the results show that DSLR cameras outperform action cameras in resolution and certain color aspects, but all cameras are capable of being used for underwater photogrammetry. The low-cost action cameras can hold their own alongside higher-cost DSLRs in spatial accuracy and can offer a more practical and cost-effective solution for underwater photogrammetry surveys.