Evaluating the 3D documentation of an early Christian upright stone with carvings from Scotland with multiples images

The documentation of cultural heritage assets requires precise and consistent approaches to preserve, analyse and monitor their integrity to future generations. The present paper deals with the 3D documentation of a unique early Christian carved stone discovered from Scotland that had been restored in the early 20th BC after accidental fragmentation. Different recording approaches are investigated; one range-based, acquired with a triangulation laser scanner and two image-based 3D reconstruction approaches, following computer vision and photogrammetric workflow with differing numbers of images. An off-the-shelf zoom digital camera was used to acquire the data, followed by 'structure from motion' and dense multi-view image matching to create dense 3D point clouds. The differences in the derived 3D models are presented and meaningful recommendations can be extrapolated for likewise surveys.