Dimensional accuracy assessment of 3D models based on photogrammetry and 3D scanner: a case study from the Museo Egizio of Turin

Digitalization techniques in cultural heritage are acquiring importance since they represent a tool to create three-dimensional virtual replicas and capture data on the appearance, geometry, and texture of historical artifacts. Photogrammetry and 3D scanning, predominant in the digitalization field, have particular features. Photogrammetry is able to reconstruct virtual replicas via multiple camera acquisitions, creating 3D models with a photo-realistic texture. On the other hand, 3D scanning achieves 3D models with higher accuracy in terms of geometry and morphology but with a lower texture resolution. This research focuses on a low-cost and open-source system based on photogrammetry, to compare the dimensional accuracy between photogrammetry and 3D scanning, using the latter as the reference. A case study involving a Roman-period Egyptian mummy from Museo Egizio of Turin (Italy) is employed to illustrate the application. The restoration of the mummy unveiled the mummy's skull, lacking its usual bandage, likely due to theft. Digitalizing the skull facilitated the study and documentation of the mummy for restoration, ensuring proper relocation and enabling museum exhibition. This study highlights the potential of digitalization and photogrammetry in preserving and presenting cultural heritage.