Deformations of Image Blocks in Photogrammetric Documentation of Cultural Heritage—Case Study: Saint James’s Chapel in Bratislava, Slovakia

Abstract

Structure from motion photogrammetry is currently one of the most frequently used technologies for the documentation of archaeological sites. Due to the relatively high freedom in choosing the position and orientation of the cameras, qualitatively different results for the reconstructed geometry can be achieved. Therefore, in the presented study, we focused on monitoring the changes in the geometry of point clouds obtained with different configurations of the camera network during the digitization of Saint James’s Chapel in Bratislava city. The changes of the tested photogrammetric variants were analyzed through comparison with scans from terrestrial laser scanning. The results suggest that caution should taken when striving for image recording efficiency, as insufficient connections between image blocks can lead to a decrease in relative accuracy, down to a level worse than 1:1000.

Keywords

• structure from motion
• photogrammetry
• laser scanning
• model deformations
• cultural heritage