Detect the differences: Cultural Heritage survey, documentation and interpretation for conservation activities

The actual greater diffusion of advanced surveying and representation tools, increasingly user friendly, represent an advantage in terms of cultural heritage digitizing and knowledge sharing, but it requires a series of consideration on the quality of the procedures adopted and the possibility of qualitatively and quantitatively evaluating the results obtained. Surveying means knowing and understanding the existing, in its geometricmorphological constructive specificities; the different methods and tools of data acquisition must be chosen with the objective of documenting and representing the real geometries, ensuring that recognition of the differences between the stratified elements, which represents the first moment of diagnostic analysis of the historical asset. Only graphical elaborations made according to these criteria, with levels of detail according to the different scales of representation, can usefully become support for conservation project and management of restoration processes. The characteristics of uniqueness and complexity of each historic building require an ad hoc design of the survey activities, tools and methodologies to be adopted, and of the forms and scales of representation. Nonetheless, it is possible to identify a general workflow of the surveying activities to obtain data that could be geometrically reliable, quantitatively controllable, comparable, and repeatable over time.