On the limits of 3D capture: A new method to approach the photogrammetric recording of palaeolithic thin incised engravings in Atxurra Cave (northern Spain)

Abstract

Rock-art recording has been significantly improved in recent years by new technologies. Nonetheless, accurate documentation of certain engravings is a challenge for these cutting-edge technologies, especially the extremely thin incised lines used in many Palaeolithic engraved motifs. In this paper, we propose a new methodology for recording these engravings with the objective of producing results comparable to the information available for Palaeolithic portable art.We are currently testing a multi-scale modelling methodology for these engravings. The objective is to produce affordable ultra-high resolution 3D models. Our methodology is completely built around close-range photogrammetry techniques, capturing scenes in increasingly higher resolutions and with different light settings. These entities are referenced to a local coordinate system allowing the overlapping of the different captures. Finally, the detailed tracings achieved from the independent higher resolution 3D models can be accurately gathered in an overall 3D model of lower resolution without geometric distortions.