Metrological issues in 3D reconstruction of an archaeological site with aerial photogrammetry

The use of aerial photogrammetry as a tool for gathering information about archaeological sites is recently growing. This trend is guided by the affordability of unmanned aerial vehicles equipped with high resolution cameras. The accuracy of photogrammetric 3D reconstructions is influenced by several factors: from the use of ground control points to flight planning and to the localization capabilities of the employed aerial vehicle. In this work, the 3D reconstruction of the archaeological site of Adulis, Eritrea, is described from planning to data acquisition and processing, with particular attention to the effect of technological and environmental limitations on the mission planning and obtained data quality. The results prove to have a reasonable and acceptable uncertainty, given the on-site difficulties and the purpose for which the data have been acquired. The main outputs of this work, (i.e., orthoimages, 3D models and digital elevation models) will constitute a base for future works related to the development of an archaeological park, accessible to visitors, and to the planning of the activities related to new excavations, such as the resulting materials handling.