To preserve a cultural asset, the main goal to achieve is represented by the conservation, which can be carried on, at first, through a preliminary” scientific program of knowledge “of the object, and the context it is referred to. In this critical moment, the most influent aspects are the interdisciplinary instruments and methods coming from heterogeneous available sources that have continuously been updated. The rich cultural heritage related to the architectural asset, at things stand, create serious problems of documentation: by using a pragmatic attitude, it is necessary to supply to include in the ordinary cultural work, methods and techniques, that on the basis of wide margins in the metric plotting, can be able to guarantee the memory as in the essential form as in the characteristics of a building. Obviously, the manufactured product’ s objective importance and complexity will inform about the opportunity or the impossibility to adopt simplified or sophisticated techniques, but if either economic sources, nor temporal ones would be enough, it seems to be appropriate to safeguard, first of all, the artistic heritage’s memory, converting the artistic work, at least, into the photographic documentation. Fortunately, the photographic picture [by using a few shrewdness] can be considered, even if a modest metric precision’s “measuring instrument” a very fruitful work’s tool. The photograph doesn’t provide an analytic study, but it is useful in order to define the manufactured product’s consistence. The first step is to establish the building’s shape and realize a basic communicable image (qualitative judgment); only afterwards, and after a precise global rating, the accurate analysis could be considered as a possibility ( quantitative judgment) and in the end it will be decided the opportunity to operate or not.