Perspective. Theories and Experiments on the 'Veduta Vincolata' (Restricted Sight)

Erwin Panofsky's work on 'Perspective as symbolic form', has had a powerful impact not only on the art critics and therefore on the artistic-historical literature, but also on the studies that deal with the theme of perspective from the scientific point of view. The reflections stated by Panof-sky in the incipit of his essay, in fact, were considered in an uncritical and superficial way to say that the perspective describes an image of the space that it represents, similar to that of the human vision only if: the eye of whoever is looking is positioned exactly in the projection centre used to generate the perspective image; the same eye remains motionless and therefore with the direction of the gaze perpendicular to the picture. This condition of observation of the perspective is known to the Italian scholars as 'veduta vincolata '. Recent studies have proved, theoretically and experimentally, that, on the contrary: the eye of whoever is looking at a perspective can move in an area around a projection centre without causing a collapse of the perspective illusion, or better, of the sense of visual depth evoked by the perspective; the eye of whoever is looking can freely move around, in every possible direction, without compromising the effects of the perspective. These studies are expounded in this paper, first of all describing the theories and the experimentations that have given the above men-tioned results. Secondly, it describes the verifications carried out on important perspectives painted on walls and entire rooms, in which the conditions of one single projection centre are respected. It also describes other works, in which appropriate solutions permit to dilate the area of the veduta vincolata. Finally, in a quick re-reading of the first pages of Panofsky's essay, this paper aims at an interpretation of it, which attempt to overcome the conflict between the advocates and the detractors of perspective as legitimate form.