The comparison of photogrammetric and terrestrial laser scanning methods in the documentation of small cultural heritage object – case study

Abstract

Nowadays, 3D models are commonly used to protect, manage and preserve cultural heritage objects and sites. Two methods are widely used: close-range photogrammetry and terrestrial laser scanning. Both those methods are burdened by the errors caused by the measurement system and physical properties of the object being under development. This investigation aimed to present the potential and limitations of using the photogrammetric and terrestrial laser scanning methods to document small cultural heritage objects. The object is a water pumping station building located in the Museum of King John III's Palace at Wilanów. It is situated near Lake Wilanowskie; hence the access to one wall was considerably limited. Data were acquired by the Terrestrial Laser Scanner Z+F 5006h and full-frame camera Canon 5D Mark II with the focal length - 17, 24, 28, 35 mm. The close-range images were processed in the Agisoft Metashape program, and the Structure-from-Motion with MultiView Stereo approach was utilised for the dense point cloud generation. The extended quality assessment analysis was conducted in the CloudCompare program, and the comparison between point clouds and cross-sections derived from the dataset was compared. The result of performed investigation shows that the point cloud generated from photos taken with a lens with a focal length 35 mm is characterised by the highest accuracy.