Surveiyng Iilusory architectures painted on vaulted surfaces

This paper addresses the problem of surveying illusory architectures painted on vaulted surfaces. The survey of a quadratura, or a painting in general, requires recording the metric and chromatic characteristics of the subject and the typical characteristics of the painted surfaces, such as soot, engravings, and giornate. Our goals are the proposal of an “optimum” quality standard for surveying curved painted surfaces and testing a method to acquire and render the data that allows those standards to be met. The test, conducted on the corridor of Saint Ignatius of Loyola rooms in Rome depicted by Andrea Pozzo, shows how the quality of the texture can be measured in terms of overall sharpness and average resolution. It is also shown how it is possible to identify some reference standards that allow the quality of the final result to be determined already in the photography phase of the project.