“OLD AND LOW-COST SENSOR” FOR MICROPHOTOGRAMMETRY. CASE STUDY: THE EMPEROR MAXIMIANUS HERCULEUS’ MEDALLION AT THE CORRER MUSEUM (VENICE)

Abstract. The microphotogrammetric survey of the roman emperor Maximianus Herculeus’ medallion, described in this report, demonstrated that, despite the use of an “old” and, nowadays, “low cost” camera sensor it is still possible to obtain a detailed 3D textured model useful for different scientific purposes and virtual enhancement. Here are presented the photogrammetric results reached with the selection of the best solutions in terms of number of images, in order to speed up the entire photogrammetric workflow and pursue the goals previously explained. This medallion is one of the most important examples of roman medallions which belongs to the numismatic collection stored at the Correr Museum in Venice. Its 3D survey was developed as a parallel step of a main project which aims to acquire in three-dimensions, with a structured light scanner, the complete roman collection of medallions. This digitization project proposes to record the volumetric information of these small archaeological remains and to realize an online virtual gallery in the web site of the museum (using 3DHOP, an open source web viewer developed by the Visual Computing Lab of the CNR-ISTI of Pisa). At the end of the microphotogrammetric workflow, a distance analysis was computed to highlight the differences between the meshes obtained with a photogrammetric approach and a structured light scanner.