## 2 Materials
### An Ancient Egyptian Bas-Relief  
The subject under examination in this study is the chapel of [PERSON], situated in a reconstructed state in the Museo Egizio in Turin since 1970. It was originally built during the reign of King [PERSON] (1479-1425 BCE) at Ellesiya, a site close to Aniba, ancient Miami, the seat of Egyptian colonial power in Nubia. The chapel was dedicated to the deified king, [PERSON] Karnak, and [PERSON] of Miami. The temple's inner layout has an inverted T-shape featuring a broad transversal hall and a rectangular niche, at the rear of which three rock-cut statues of the deities venerated in this chapel are situated. The inner walls are decorated with scenes in bas-relief, once painted, depicting the king making offerings to both Egyptian and Nubian deities. Scenes including the images and names of [PERSON] were defaced during the reign of [PERSON] (1351-1334 BCE), but they were later restored under [PERSON] (1279-1213 BCE). In the medieval Christian period, the chapel was transformed into an oratory.  
Due to the construction of the High Dam at Aswan (the Sadd el-Ali) and the subsequent flooding of the Nile valley in the south, almost all of Nubia was lost under the waters of the reservoir. As one of the historic monuments that would have been submerged, the Ellesiya chapel was removed from its original location in 1965 and the cut-out blocks bearing reliefs and hiergoglyphic texts were transported to Turin, where they were partly reassembled in 1969-70. These operations happened in the framework of the international UNESCO Campaign to Save the Monuments of Nubia, during which the Ellesiya chapel was officially gifted to Italy by the Egyptian government as a token of appreciation for the financial and logistical help provided by Italy to said campaign [28; 29]. The Ellesiya chapel has been documented a few times in the past. A complete black and white photographic survey--together with documentation of the architectural and epigraphical features--was carried out before the chapel was removed from its original location [30].  
After the reconstruction of the chapel in Turin, several photographic campaigns were undertaken to document the structure and its diverse features in the museum [31; 32].  
In 2023, the Centro per la Conservazione ed il Restauro dei Beni Culturali (CCR) \"La Venaria Reale\", Italy, carried out a comprehensive documentation campaign based on the use of advanced technologies, including high-definition multiband imaging to detect pigment remnants that have become invisible to the naked eye, such as Egyptian blue. This project facilitated the testing of V-RTI, a digital photographic workflow combining principles from RTI and photogrammetry to enhance surface visualization and improve the documentation's level of detail, particularly in confined spaces like the bas-relief under study in the Ellesiya chapel (Figure 2).  
Figure 2: Interior view of the Ellesiya chapel, Museo Egizio, Turin. The red rectangle indicates the selected wall for this case study.  
The current lighting setup illuminates the chapel's walls mainly from the floor, altering the perception of the raised relief hieroglyphs, figures, and other iconographic elements. To accurately depict convex and concave forms, especially of a rather shallow bas-relief, the present case study underscores the importance of selecting top lighting, ideally with an incidence of 45\({}^{\circ}\) from the top, which not only appears more natural and less ambiguous but is also the conventional light incidence in the context of epigraphical documentation.