The Quicksands Archaeological Survey team will employ two distinct photographic techniques to document the archaeological sites in the project area: multi-image photogrammetry and 360֯-degree panoramic imaging. Each technique results in high-resolution imagery suitable for archaeological analysis, while at the same time capturing the archaeological sites within the context of their surrounding natural environment. Additionally, the two distinct viewpoints created by these approaches provide immersive experiences for viewers, allowing them to virtually experience these remote locations.
Multi-image photogrammetry creates three-dimensional representations of objects using multiple overlapping images captured by a series of adjacent camera positions. The overlapping images are processed with computer software to generate a three-dimensional mesh model by comparing and aligning the matching points within one image to the same points in subsequent images. Model texture is derived from the same imagery resulting in a very realistic and accurate depiction of the site. The technique has been widely employed by the maritime archaeological community for its ability to represent three-dimensional objects and the speed of data collection as compared to traditional drawn archaeological site maps (McCarthy 2019).
The project’s research team anticipates that the archaeological sites in the Quicksands are scattered over areas much larger than the vessel’s original structural dimensions. To aid in data collection, research team members will use diver propulsion vehicle (DPV)-mounted cameras for photogrammetric image collection. DPVs will be outfitted with either a single downward-facing SLR camera in an underwater housing or dual-housed cameras separated on a cross bar to increase image density. Techniques developed by University of Miami researchers for large area data collection of coral reef imagery will ensure suitable image coverage to achieve project objectives during the current-limited diving conditions.
In concert with photogrammetric documentation, researchers will employ a tripod-mounted 360-degree panoramic camera system. Developed by The Ocean Agency and XL Catlin Seaview Survey, the camera system consists of a digital camera and ultra-wide angle lens in an underwater housing. Following initial characterization dives, team members will set up the camera system at diagnostic locations around the shipwreck sites. Each 360-degree node requires 6 photographs taken at a 60-degree angle from one to the next. Following imagery collection, panorama stitching and virtual reality software creates immersive tours allowing researchers and the public to virtually revisit the shipwreck sites.
Office of National Marine Sanctuaries maritime heritage coordinator and research team member Brenda Altmeier levels the 360-degree panoramic camera before photographing the Tonawanda shipwreck off Key Largo. Image courtesy of the Office of National Marine Sanctuaries. Download image (jpg, 14.5 MB).
McCarthy, John, Jonathan Benjamin, Trevor Winton, and Wendy van Duivenvoorde
2019 The Rise of 3D in Maritime Archaeology. In 3D Recording and Interpretation for Maritime Archaeology. McCarthy, J., Benjamin, J., Winton, T., and van Duivenvoorde, W., editors, Coastal Research Library 31, Springer, Cham. https://doi.org/10.1007/978-3-030-03635-5_1
