| Documentazione 3d dei capitelli alto-medievali (Aosta) |
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Company Name/Author: Itabc-cnr, P. Salonia's team Reference url: www.itabc.cnr.it www.arkis.it Project date: 2006-2008 Project place: Sant’Orso Collegiata, Aosta, Italy Used product: ZScan Used camera: Nikon D200 calibrated Used lens: Nikkor 24mm Strip number: 890 circa Baseline: 100 mm Related Document:  3d documentation of the alto-medieval capitals situated in the cloister of the S. Orso (Aosta)
Abstract: Archaeological and architectural artefacts reconstruction for their preservation, safeguard and valorization place technicians or researchers the decision on which technology to apply for data capture, digitization or final dissemination and visualization of results. The different new survey technologies play a leading role in the process of knowledge and documentation of the cultural and environmental heritage but so often the choice is linked mainly to the economical resources available. Moreover each one of them has advantages but also limits referring to the elaboration, management and possibilities. Low cost close range sensors, based on images capture and RGB point clouds extraction from pixels trough trinocular image rectification and feature matching, offers a quick and at the same time a high quality data capture, within millimetric accuracy, for 3D reconstruction and inspection of the artifacts, compared to laser scanner technology. The survey of the capitals of S. Orso Cloister (completed in 1113) in Aosta, Italy, which is one of the most and well conserved medieval cloister in the Alps, has been the chance to enlighten and solve many of the critical aspects of the application of 3D scanning without laser owed mainly to the image capture as planning the shots so to cover all the undercuts or covered parts of the figures, light, shadows and color control, color balance and equalization between different shots, different focusing for coupled pillars, or clouds registration as the system has been thought for quasi-planar surfaces and linear geometrical development. Three main objectives, first to identify the present geometry, with particular reference to their construction details as to provide reliable data for physical and structural pathology analysis, second to record the actual color value, finally to develop a documentation methodology based on digital surveying techniques. The 3D digital model of the 37 marble capitals obtained, completely fulfill the Public Administration demand of a scientific reliable and accurate range measurements useful for their eventual reconstruction in case of physical and structural damage. Moreover they represent the closer step for a multiscale survey project of the cloister and the construction of a 3D database within organized information in layers of deeper structural and iconographical complexity and detail. Finally is to underline the low cost of this technology which offer to peripheral museums or small Public Administration the opportunity to plan surveys and preservation of own artefacts otherwise not possible if more expensive technologies and methodologies, as laser-scanner, are involved, that question us on the ethical responsibilities of the use of too expensive hardware in Cultural Heritage knowledge. Gallery: |
