This 3D model shows Gozo’s Azure Window, combining in one model both the site prior to its collapse in 2017, together with the underwater remains of the collapsed site. The underwater photogrammetric model was created for a geomorphological study and public awareness project, utilising cameras and lights mounted on diver propelled underwater scooters. Some 25,000 photos were required for this model, and the depth of the site ranges from just below the sea surface down to roughly 60m. The pre-collapse model utilised drone footage captured prior to 2017.
More information on this study can be found on http://dwejra.net/
The journal paper is available here: https://www.sciencedirect.com/science/article/pii/S0169555X2200143X?dgcid=author