This study concerns architectural representation, and it focuses on the Quadratura issue: an illusory architecture painting where perspective creates the illusion of spatial depth on a flat surface. The main subject of this work is the study of the perspective scenes frescoed in the yards of historical building, during the 18th century in northern Italy, especially in Bologna; they represent architectural scenes, placed at the end of a promenade through the building. One of the most interesting example of these perspective frescoes in Bologna has been designed in 1761 by Antonio Galli Bibiena in Palazzo Vizzani's yard. This study aimed to approach a digital 3D-reconstruction of the scene, based on an accurate documentation and a combination of architectural survey techniques. Finally the digital reconstructed scene can be video-projected on the wall: it can simulate a viewer's eye guided across the building towards and inside the scene.
TopIntroduction And Framework
The perspective scenes frescoed on the courtyards of some of Bologna’s historical buildings are a particular “framing” of cultural heritage. This essay talks about the knowledge of cultural heritage, in particular of perspective-frescoed walls, focusing on the best ways to portrait them and communicate them to the people. This is of specific importance because the majority of these pictorial works are either unknown or placed in hidden locations. Also, many of these scenes have been lost through the years, due to the exposure to the elements and due to human neglect.
After having screened several examples of perspective-painted yards, frescoed in the city of Bologna between the 17th and the 19th centuries, the study targets the perspective fresco created by Antonio Galli Bibiena in Palazzo Vizzani; the goal was to build a digital 3D-reconstruction of the lost scene, using a previously-executed accurate analysis and a combination of different architectural survey techniques.
These kinds of perspective canvases, placed at the end of a promenade running through the building and mimicking the wings of a theatre stage, are to be considered a sort of urban stage design. These buildings were mainly senatorial buildings, located on the main streets, and they represented an expression of the local power. The aristocratic families of the times used to hire artists to paint the yards and the apartments of their buildings, with the aim of creating a unique, customized-looking building within the city scenario.
It was important to understand how the author created the entire composition, and how in the 18th century people were attracted inside the building, how they were encouraged to explore a semi-public area (such a courtyard), passing through a perspective telescope, to admire, in the end, a frescoed wall. Once the viewers arrived in front of the fresco they could see a space without boundaries, in a rhythmic succession of spaces.
The Quadratura genre is an illusory painted architecture where the perspective creates a trick of spatial depth on a flat surface by employing the technique of proportional foreshortening and by using a realistic rendering of light. The author needed to have extraordinary painting skills and knowledge of optics and geometry.
In a perspective composition objects are scaled in relation to the viewer and everything converges to the vanishing point: the beholder, by standing in the centre of the perspective projection, can imagine a limitless space, where real and fictional worlds merge. A particular but effective definition of the power of perspective might be:
The convention of perspective centres everything on the eye of the beholder. It is like a beam for a lighthouse […] Perspective makes the single eye the centre of the visible world. Everything converges on to the eye as to the vanishing point of infinity […] every drawing or painting that used perspective proposed to the spectator that he was the unique centre of the world. (Berger, 1972)
For centuries, especially from the Renaissance, many scholars were intrigued by the power of perspective applications, and many of them wrote treatises that helped to understand this kind of works: for examples those of Sebastiano Serlio, Jacopo Barozzi da Vignola, Andrea Pozzo and (most important all for this case study) the treatise of Ferdinando Galli Bibiena (Galli Bibiena, 1711). By analyzing these treatises it is possible to understand the enigma of perspective projection, guessing how the entire artistic work was created.
The subject of this work was selected from several perspective scenes, including many of them in critical conditions; have been found about fifteen examples of painted yards in Bologna, usually framed by an arch or painted on an entire wall, such as the yard of Palazzo Monti Salina and the yard of Palazzo Vizzani, painted by Ferdinando and Antonio Galli Bibiena.
At the time Bologna was a vibrant environment: it was the headquarter of both the Archiginnasio and the Accademia Clementina (The Academy of Fine Arts) and therefore many artists could receive commissions from the aristocracy and from the royal Courts.
The Bibiena dynasty paved the way for a unique cultural koinè. They were architects and stage designers working during the 18th century, and they became very famous for their unique skills.