Low-cost photogrammetry solutions for surveying confined underground spaces: testing the traditional set-up against 360° camera on Tombs of the Kings archaeological site

This study explores low-cost photogrammetry solutions for surveying confined underground spaces, focusing on Tomb 7 at the UNESCO World Heritage Site, Tombs of the Kings in Paphos, Cyprus. The research, part of the ENGINEER project, compares traditional photogrammetric methods using frame cameras against a 360° multi-lens camera. The aim is to identify reliable, low cost methods for 3D documentation of archaeological sites, which can be used for structural analysis and systematic monitoring. Three photogrammetric acquisition methodologies were tested: handheld with frame camera, standard with frame camera, and relaxed with 360° camera. The study evaluates the accuracy of these acquisition methods by comparing dense point clouds generated from each dataset against a reference dataset obtained via terrestrial laser scanning (TLS). Metrics such as cloud-to-cloud distance, roughness, and point cloud density were used for comparison. Results indicate that while the 360° camera offers ease of use and high data density, it also introduces more noise and variability. Traditional methods, though more time consuming, provide more consistent and accurate results. The findings suggest that combining both approaches could optimize data quality and acquisition efficiency, making the 360° multi-lens camera a viable low-cost photogrammetry option for heritage documentation.