Tecniche fotogrammetriche digitali per la conservazione e il restauro di apparati decorativi

Abstract

The paper describes the photogrammetric survey of the frescoes in the church of Saints Cosma and Damiano in Cefalù and in the “Sala della Fontana” of the “Palazzo della Zisa” in Palermo. The use of the digital photogrammetry, besides guaranteeing the precision and the reliability of the measurements, allow a simplification of the operations for investigate the state of conservation. The photogrammetric operations have been carried out in different way in consideration of the different logistic situation. The interior of the Church of the Saints Cosma and Damiano didn't introduce particular problems of accessibility; the frescoes were situated in an enough favourable position for topographic and photogrammetric survey. In the “Sala della Fontana” the presence of the scaffold, used by the restorers, has limited the availability of spaces and visibility of the frescoes. The photogrammetric process has been directed to the production of orthoimages and 3D photorealistic models. The orthoimages have been used to realize thematic maps of executive techniques, state of conservation and interventions of restauration.