High accuracy images and range based acquiring for artistic handworks 3D-models

The research topics and the applications in the Geomatic area are often connected to the land knowledge and management or to human artefacts usually studied and analyzed from expert of other areas. When these subjects are a part of the Cultural Heritage the survey methodology for the documentation and the knowledge need to consider the final users (belong to different disciplines), in order to realize correct descriptive products suitable for all the actors involved in the preservation and the safeguard of the Cultural Heritage. During the last decade one of the important aim related to the cooperation between the Geomatics group of Politecnico di Torino and the experts working on archaeological sites is to join the new Geomatic methodology and techniques in order to realize documents and products, usable by the specialists, aimed to the archaeological site knowledge and documentation. The past applications were focused on the ancient city, from the urban scale through the archaeological evidences up till the architectural elements. The paper deal with the last experiences of the research group relating to two important archaeological objects. In particular the archaeological artefacts are figurative relief featured by small dimension, carved in the marble and belonging to two architectural elements; the subjects are two theatrical masks, one comical featured and the other tragical. In order to aid and support other analyses involving restoration strategies one of the goals of the last expedition was the documentation, the survey and modelling of the artefacts. According to the complex shape of the theatrical masks, and in order to obtain all the information requested for a correct survey documentation, a triangulation-based LiDAR system was employed (HandyScan 3D- model HZ). Moreover, since the LiDAR survey was performed on the more complex decorated surface (theatrical masks) in order to achieve a complete 3D model of the marble blocks a photogrammetric survey was realized. In the paper some topics are going to be described, highlighting advantages coming from multi-sensor data fusion techniques, both for obtaining multi-scale models and for general accuracy improvement. Some discussed topics are: The acquisition phases and the obtained results of the 3D HandyScan survey, the photogrammetric processing steps and the realized products, the assembling and integration of the different kinds of data, the 3D representation and the photorealistic modeling phases