A Geometrical Analysis of Multiple View-Point Perspective

Following a series of accolades, including the RIBA President’s medal, Joanna Rapp’s dissertation, “A Geometrical Analysis of Multiple View-Point Perspective in the Work of Giovanni Battista Piranesi” is now available in print.

This paper, which is both an exquisitely illustrated account of restitution and an original piece of research, adds significantly to our understanding of Piranesi’s work and his use of perspective. In its original form, as research carried out while Joanna was a student at the University of Westminster, it was already recognised as offering important new observations regarding the underlying construction of Piranesi’s drawings.

That Piranesi’s drawings are ‘inconsistent’ in their use of perspective is well documented, but this study not only shows us to what extent perspective has been manipulated, it also shows us exactly how. Most striking is perhaps the scale of the distortion revealed in Piranesi’s drawings but implied is also a critique of the notion that Piranesi’s drawings are fragmentary and incoherent, demonstrating instead that there is consistency in the way perspective has been distorted.

Below is quotation from Joanna Rapp’s own account of the original dissertation. The published paper can be found in issue 6 of the Journal of Architecture (December 2008) published by Routledge.

“This paper is a study of the eighteenth-century Italian artist Giovanni Battista Piranesi. Known predominantly for his Carceri etchings and reputedly a colourful and interesting character, Piranesi was also one of the great recorders of eighteenth-century Rome. In my dissertation I have attempted to show how, in addition to being a highly skilled draftsman, he also manipulated reality in these drawings to enhance, (or falsify) our view of Rome. To do this I have applied a now little used technique known as “restitution”. A process pioneered by the eighteenth-century German mathematician Johann Heinrich Lambert, restitution uses descriptive geometry to derive the metrical proportions of objects depicted in perspective. This analysis clearly shows how the artist manipulated perspective to control its visual impact on the viewer. Many sources talk about the artist’s manipulation of reality, referring mostly to exaggeration of scale, moving buildings, falsifying proportions, perspective foreshortening and the combining of different viewing positions; but few offer any precise analysis. The benefit of such a study, is to provide an insight into the process and thinking behind Piranesi’s drawings.

Piranesi’s primary concern was for the quality of the drawing and he was, it seems, prepared to manipulate the conventional rules of perspective in order to produce a more believable and compelling representation. In so doing he converted the traditional topographical view and instead of just providing factual information he used it as a tool to interpret reality and, in a very subtle way, influence our understanding of it. In this study I present some specific examples of Piranesi’s drawings. He composed his perspectives with such precision, that I was able to employ a precise geometric tool to analyse his work, and although I have clearly proved that the images do not reflect reality (from a single viewpoint), it has enabled me to demonstrate that they are distorted using precise geometrical constructions. My aim has therefore been to present a specific and detailed analysis of his technique and to reveal the sophisticated approach to perspective employed by Piranesi.”  (Joanna Rapp, 2007)