Una figura mancante: la legge di degradazione delle grandezze apparenti

estratto da:

Migliari, R. Baglioni, L. Fallavollita, F., Fasolo, M., Mancini, M.F. Romor, J., Salvatore, M. Piero della Francesca, Edizione nazionale del De Prospectiva Pingendi, Edizione critica del codice 616 Bibliothèque Municipale, Bordeaux. Volume III.B, Disegni, Istituto Poligrafico dello Stato, p. XIII-XXVI.


read more …

proprietà_della_prospettiva_lr

Ecdotica dei disegni del «De prospectiva pingendi»

estratto da:

Migliari, R. Baglioni, L. Fallavollita, F., Fasolo, M., Mancini, M.F. Romor, J., Salvatore, M. Piero della Francesca, Edizione nazionale del De Prospectiva Pingendi, Edizione critica del codice 616 Bibliothèque Municipale, Bordeaux. Volume III.B, Disegni, Istituto Poligrafico dello Stato, p. XIII-XXVI.

read more …

codice_latino_023

Experimenting with Perspective. Particular Relationships between the Image and the Mind

casale_andrea_fig06

 

The geometric certainty of perspective presents the Renaissance artist with a choice: should the work create the illusion representing the concrete, sensible world, or, on the contrary, should it portray the transcendent, speculative, abstract world of thought? This dichotomy would substantially characterise the culture of representation in the West from the Renaissance on. Perspective drawing becomes both the perfect experiment and the tangible testimony of this choice. For this reason, the phenomenon of perspective demands a unique analysis that considers this duality, since the informational intent reflected in the system for its realisation is different.

read more …

On the Interpretation of Architectural Perspective

fasolo_marco_fig04

by Riccardo Migliari, Marco Fasolo and Leonardo Baglioni

This contribution identifies the recurring problems in geometric restitution of architectural perspectives and proposes a working method. The inverse problem of perspective proposes the reconstruction of the fundamental elements in space. However, when the observer and spectator are not congruent, a question is raised: should we reinstate illusory space in realistic or surrealistic way? To answer this question, a new approach to restitution is suggested, which is organized into three moments: visual analysis, geometrical analysis and three-dimensional reconstruction, and critical interpretation.

read more …

Textual Criticism of Drawings in Historical/Scientific Treatise on Representation: the Caput in De Prospectiva Pingendi

fig_01

by Leonardo Baglioni, Marco Fasolo, Matteo Flavio Mancini

The proposed article aims to provide a methodological contribution to reading historical/scientific treatise on representation. In philology, textual criticism is the critical analysis of literary texts aimed at a deep understanding of the text and the
author’s intentions. In historical/scientific treatises on representation, the work is composed of two “texts” of equal importance: one is literary, the other graphic. In these cases therefore, textual criticism should be applied to both “texts” at the same time. The case study chosen to investigate the potential of the research method is the first illustrated treatise dedicated to perspective: De Prospectiva Pingendi by Piero della Francesca. While this is a work aimed at painters, the theoretical principles and applications of perspective are also addressed, contributing to a definition of the scientific basis of descriptive geometry. The bibliography is very rich, including essays by C. Winterberg (1899), G. Nicco Fasola (1942), M. Kemp (1994), and K. Andersen (2007). However, it should be noted that graphics that could explain the reasoning behind Piero della Francesca’s drawing are not always included, especially in critical editions. Among the pages of the treatise, proposition 8 in book III holds particular importance for the proposed investigation. Here, Piero constructs the perspective of a human head (Figure 1), which is first positioned straight (frontal position), and then looks upwards (generic position).
This proposition represents a major step in that for the first and only time, the author addresses the theme of free forms. To read this proposition critically, it is necessary to refer to a hybrid digital model (polygonal mesh, subdivision surface,
and NURBS) developed by studying the codices housed in the Palatina Library in Parma and the Municipal Library in Bordeaux. Construction of the digital model allows us to understand both Piero’s refined spatial reasoning and its relative plane rendering (Figure 2) in an original reverse path that highlights the scientific nature of the entire treatise and the potential of digital representation as applied to the textual criticism of drawings.

read more …

Perspective as a representation method

Perspective as a representation method_01

by Riccardo Migliari, Jessica Romor, Marta Salvatore

Traditional teaching of perspective wants the perspective image to be generated with various procedures, which make use of the orthogonal projections of the object that is to be represented. It is nevertheless well-known that the perspective image also can be generated autonomously, that is to say, without resorting to the orthogonal projections, as part of a method known as ‘central projection’.
In many schools and in many textbooks these two paths, which both lead to the genesis of the perspective image, remain distinct, as if they were two different methods, if for no other reason than their vocation; the first, also called, improperly, ‘the architect’s method’, which only focuses on the achievement of the result: an image similar to the natural vision of the space; the second, conceptual, devoted to the study of the central projection in itself and its applications of projective nature: from the genesis of the quadrics to the homography.
In the Roman school, yet, as from the second half of the twentieth-century, it was attempted to bring together into one single method the two above-mentioned approaches to perspective, giving a happy ending to a history that for centuries has seen the perspective split between artists and mathematicians.
In this paper, after a short presentation of the characteristics of the ‘perspective as a representation method’, is highlighted the advantages of the aforesaid method in academic teaching. These are, precisely: first of all the possibility to see in the perspective the generalization of the representation methods, following on from the thought of Wilhelm Fiedler (1832-1912); then the possibility to easily add the concepts relating to infinity (points, straight-lines and the improper plane); and, the possibility to establish a relationship that is not general, but operational, between the graphical perspective and the digitally rendered perspective.

read more …

Architectural Perspective: digital preservation, content access and analytics

National research (PRIN 2010 – 2011)

The objective of the research project is the preservation, the study and the popularisation of the Architectural Perspectives (AP). The project pursues this aim through the development and the application of the most advanced communication technologies (ICT). The main topic of this research project, namely the Perspective, has a strongly European character, and as such it is acknowledged and shared.
Perspective is transversal in Europe: worldly speaking, because it starts from the evidences of Roman wall paintings, arriving at the Baroque illusions; spatially speaking, because there is no region or European language which has not employed the Perspective, often borrowing solutions from one country to another; culturally speaking, because Perspective is the synthesis of science and art, and it is always developed interchanging the geometric and projective theoretical speculations, and the practising of the drawing and the architecture.
The Perspective, which this research project considers a privileged case study, is that of the geometric structures that, painted onto walls (2D) or carried out in  dimensions (3D), are able to evoke an illusory depth of the architectural space. A good example of the 2D kind is the fresco painted by Agostino Tassi at Lancellotti Palace, in Rome (1621 – 1623).

Italy and all Europe have a cultural heritage of Architectural Perspectives (AP) which extent, complexity and historical importance, for science and for art, is,currently, inestimable.
This project foresees, among its main activities, the study and the validation of survey techniques and procedures, of registration, of classification of the Architectural Perspectives, at the end of achieving a first global valuation, and inductive, of the Italian cultural heritage. This also explains the very high number of Operational Units and their distribution on the territory.
Among these techniques is the Photography in ultra high resolution, which this research project will give a reliable measurement quality, such as to guarantee a documentation that is useful for the preservation. The urge of this kind of experimentation is evidenced, just to cite one example among many, by the fragile and precarious condition of Pompei.
The gathering and the diffusion of the data, do also have another value, because all these Perspectives are ‘treatises without words’ of geometrical science and their comparative examination is therefore an innovative tool for the development of the knowledge at historical scientific level. In particular, the project foresees the application of statistical methods to the analysis of the Perspective structures, like those already tested with success at the measurements of the double ration in the frescoes of Augustan age.
The digital techniques for the Perspective rendering and 3D modelling will give us the opportunity to study the proportional, compositional and stylistic aspects of the represented illusory spaces. These features do often have close relationships with the environment that houses the Perspective scenes, as these reconstructions highlight. The 3D documentation will also be useful to ensure the diffusion of the results.
Although the architectural Perspectives have always amazed the non-expert visitor, these kind of Perspectives are still not very well-known, maybe also because a systematic study, like the one this research project would like to contribute to, has never been undertaken. It is therefore not the least important part of this research project, the experimentation and the validation of innovative techniques of broad-spectrum communication of the essential data, collected and interpreted. With this objective in mind, and taking advantage of the experience matured through the previous research projects (2005 and 2008), techniques of interactive navigation of the spaces will be used, as well as techniques of Augmented reality implemented on tablets and smartphones.

Results

Volume I (1st of 3) … read or download

Perspective: Theories and Experiments on the “Veduta vincolata” (Restricted Sight)

figura_13

by Riccardo Migliari and Jessica Romor

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 Panofsky 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 ‘vedutavincolata ‘. 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 mentioned 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 vedutavincolata. 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.

16TH INTERNATIONAL CONFERENCE ON GEOMETRY AND GRAPHICS©2014 ISGG

read more …
download the article