Integrated 3D acquisition of complex wooden artefacts: The Piffetti's library in Qurinale palace (Rome)

Integrated surveying with active and passive systems is a well-established process for understanding artifacts at different scales and levels of complexity. But some acquisition problems still exist, related to the presence of non-optically cooperating materials, reflective surfaces, and non-homogeneous and uncontrolled illumination conditions. Especially in these cases, the integration between different 3D acquisition techniques allows us to test the response of different instruments concerning the boundary conditions, going to compare the results. This activity highlights the pros and cons of each technique, identifying the right balance for future applications with the same conditions. The case study analyzed in the article is the Piffetti Library, a wooden work from the first half of the 1800s present at the Quirinale Palace (Rome). The artifact shows multiple levels of environmental complexity (small space with movement constraints and uncontrollable light), and it is composed of several wood pieces with a very glossy finish. The presence of shelving, free-form surfaces, and sculptural details requires careful planning to survey the artifact with consistent resolution. The use of different active and passive acquisition methods is tested, defining an integrated methodology coherent with the complexity of the artifact and the context in which it is positioned. The dual purpose is to define a possible replicable protocol, arriving at the definition of reliable 3D data for subsequent analysis and virtual reconstructions.