Abstract
The chapter contains considerations and methods of analysis of data acquired using modern surveying technologies, applied to cultural heritage. Three case studies are carried out. They are different in type of monuments, aim of survey and survey techniques used. The large amount of data acquired through innovative techniques of photographic survey and laser scanning requires an adequate process of “discretizzazione”. It will change an uncritical “total survey” into a selective and effective analysis and communication process. An excess of information could distract from the actual purpose of survey, and it could provide the illusion of a comprehensive understanding of the monument. Actually, the real knowledge does not come from the amount of data acquired but from the ability to analyze them, to relate and communicate to potential users.
TopBackground
This chapter develops on three different levels: historical and iconographic analysis; semiotics and graphics; technical and operative experimentation.
From an historical point of view, the Castellion in St. Niceto and the Cattolica in Stilo belong to the time of Byzantine domination in Calabria (554-1060). The subject has been treated by many scholars cited in references (Bozzoni, Minuto, Venditti, Venoso and others, about the Byzantine religious architecture; Martorano, about Castellion in St. Niceto). However, these studies are largely historical and with little attention to the survey, the representation and graphic-morphological analysis. The representations of these monuments, available in the scientific literature, show traditional surveys and drawings, often summary.
The Church of Piedigrotta in Pizzo Calabro has a more recent history, while being culturally linked to a hypogeous tradition, which is common in the region since the Byzantine era. The few historical information are taken from the publications listed in bibliography (Costa, Malferà). The bibliographic sources generally have no drawings and are rich of photographic illustrations. In 1989, a private company1 specialized in instrumental survey realized a photogrammetric survey integrated with total station. Other drawings, dating back to the years 1996 and 2007, illustrate surveys conducted with traditional methods, in the occasion of two redevelopment projects of the site.
The laser scanner survey proposed in this chapter is the first realized on the monument with advanced instruments and it is the most accurate representation currently available.
Key Terms in this Chapter
Photos Rectification: Digital or analog elaboration that distorts the photographs to get orthographic views.
Photo Modelling: Digital processing that allows obtaining a point cloud using several photographic images of an object.
Discretizatione: Critical process of data selection, aimed at highlighting the relevant information and omit redundant ones for a specific objective.
Point cloud: Set of points that define a three-dimensional model of an object. Each of these points is identified by its position in space and its colour characteristics.
Total Survey: Surveing process that captures all the features of the object without selecting data.
Laser Scanner: Advanced instrumentation for survey of objects. The three-dimensional model obtained will be a point cloud.