Chapter 1: The Arrow in the Eye

Kubovy’s Thesis: “In this book, I propose yet another, a DELIBERATE discrepancy between the viewer’s actual point of view and a virtual point of view

experienced by the viewer on the basis of cues contained in the perspectival organization of the painting”

He begins by showing the importance of perspective and relates Mantegna to Albert who expects the audience to realize the metaphor of arrow in the eye

(many painters put the vanishing point behind the eye of the main character in a painting. He then introduces his thesis: renaissance painters introduce a

discrepancy between audience's actual point of view and point of view from which the painting was to be felt.

Press to continue…

Chapter 2: The Elements of Perspective

-In this chapter, Kubovy discusses the camera obscura which places the eye at the center of projectionwhen you look through the pinhole, but that only gives you a 180 degree field of view.

-3 geometric properties of central projection: 1- the perspectival image of a straight line that does not pass through the center of projection is always a straight line. 2- the perspectival images parallel lines that arealso parallel to the picture plane are parallel to each other: the perspectival images parallel lines that that are not parallel to the picture plane converge onto a vanishing point (which is not necessarily within the picture). 3- the location of an object point cannot be determined uniquely by its image, but you can reconstruct the central projection, its plan and elevation, and thereby solve the problem of perspective.

Picture plane

Pinhole lens

Principle ray

Projecting ray

Chapter 3: Brunelleschi’s Peephole and the Invention of Perspective

“When Brunelleschi invented perspective, and when he sought the commission for the erection of the copula…he may have invented a trick to paint pictures in perspective without having developed the underlying geometric theory, and he may have come up with methods to erect a tall copula without having a rigorous rationale to offer….perhaps he allowed people to infer that he knew the process more conceptually than he really did…As a result, he allowed people to think him mad rather than present his plans for the copula…Thus I believe that Alberti, and not Brunelleschi, invented perspective as a communicable set of practical procedures that can be used by artists.”

Brunelleschi knew how to do it, he just didn’t know how to explain it….

He refused to tell his partner anything!

Then they both got mad and had a fight…Professor Kubovy explains why this happened:

Chapter 4: The Effectiveness of Brunelleschi’s Peepshow

-Projective surrogates- conventional and non-conventional (projective or replicative) are characterized by the theoretical possibility of the surrogate becoming more and more like the original until it is indistinguishable from it

So, Brunelleschi’s use of the peephole in his first demonstration was instrumental in producing a compelling experience of depth for two reasons: first, it increased the effectiveness of the illusion by forcing the viewer to place his or her eye at the center of projection (thus making the picture a projective surrogate); second, it reduced the viewer’s information regarding the flatness of the picture plane.

-Lenses- circle of confusion (the image of a point on an object is a circular region)- eyes change size of pupil with the iris, cameras change aperture size with focus- eye changes shape to accommodate to the object focusing on, a camera zooms.

-The reason we do not see vivid depth in pictures (whether viewed with one eye or two) is not because they fail to fulfill the necessaryconditions for such perception, but rather because pictures bear two different kinds of incompatible information, namely, information about the three-dimensional scene they represent, as well as information about their own two-dimensionality.

-We see in stereoscopic vision (both eyes- allowing for perception of depth)

Chapter 5: The Robustness of Perspective…

Is the violation of our geometric expectations by our perceptual experience.

It is unnecessary to view a picture from the center of projection to see an undistorted version of the scene it represents.

Fails when “the spectator is unable to see the painted surface, qua surface.” (Pirenne) In other words, if the subjects can see the picture plane, perspective is robust, if they Cannot, perspective is not robust.

Although there are a few exceptions: those of ‘following’ pictures…..They are visually unstable, and therefore are not robust

also trompe l’oeil (eye foolers)

Chapter 6: Illusion, Delusion, Collusion, and Perceptual Paradox

All other things being equal, the further away an object (of constant angular substance) seems to be, the larger it will appear.

If one stimulates sensory receptors in a nonstandard way, one invariably experiencesAn external object that would stimulate the sensory receptors in a similar fashion.

Emmert’s Law:The sized of the object you see when you experience an afterimage is directly proportional to the perceived distance of the surface at which you are looking.

Unconscious inferences:

There is NEVER “false belief or conception” when we look at art.

Delusion=perceptual error Illusion=awareness of perceptual error

Perceptual paradox:Division of labor in our perception- motion and location in space are different. We experience any contradictions between then as illusion.

What is interesting about trompe l’oeil painting arises in our minds after the painting Has ceased to trompe our yeux; it is when we have ceased to be the unwitting targets of a practical joke and we have decided to reflect upon the experience we Have just gone through.

Trompe L’oeil:

Extrinsic vs intrinsic

Mental collision (with the artist-not seeing what he intended)- but eventually you do, like with this vase.

We experience illusionBecause we are in collusion With the artist.

“Painted Violin” by J. van der Vaart

Chapter 6 continued

Chapter 7: Perceiving the Window in order to see the World

Visual system does not assume the observer’s vantage point is the center of projection, Otherwise there would be no robustness of perspective.

To do this, you need 2 hypothesis: 1-rectangulairy (lines that seems perpendicular are)2- parallelism (lines that seem parallel are)

The mind’s eye will find and fall onto the optical axis and compensate for any distortions. (i.e.-no matter where you sit, the view is not distorted!)

Why we perceive the distortion of a picture in a picture1-We can only compensate for one surface at a time2-We are not free to chose which surface will control the processOf compensation.

Forks and arrows: (Perkin’s laws)

arrow

fork

Chapter 8: The Bounds of Perspective: marginal distortions

Marginal distortion= when pictures looked distorted from every angle except the center of projection

We are comfortable with perspective drawings only if the scene the encompass does not subtenda visual angle greater than we would encompass in our visual field.

The projections of objects that fall within our field of view, all obey Perkin’s laws.

Our visual system is completely intolerant of variations to a sphere….if not on the optical ray, when in perspective, they should appear as ellipses….but they never do, artists have just accepted them as acceptable.

As long as the picture plane is parallel to the important surfaces of the objects representedNone of the features of these important surfaces is lost by moving the center of projection.

Perception comes first…before perspective (geometric rules)

The only way to match the bundles of light rays from the facade and the picture exactly is to Elevate the viewer to the height of the center of projection.

Vs.

Chapter 9: Why was the Brunelleschi window abandoned?

1- because it was wieldy2- it had a “gimmicky” effect (mere entertainment)

-once we learn the trick, its not interesting anymore-good art (as with theater), when you learn the tricksit only intrigues you further.-only one insight….boring….-so: gimmicky if= 1 vulnerable to technical disclosure

2demand constrained conditions of observation 3 accompanied by the suggestion that the illusion is the principle experience to be had

3-robustness of perspective: because if it, peepholes are not neededto experience a compelling illusion of depth - Leonardo’s “Last Supper” uses the robustness of perspective to make the viewer feel spiritual elevation….the center of projection is 83 feet in the air, and because the viewer will put his mind’s eye on the center of project (as discussed in ch 5), elevation is felt.

Chapter 10: The Psychology of Egocenters

The boundary between the world and ourselves is very flexible

Optic array contains two kinds of information: 1-layout of objects in the environment (exterocepive info) 2- about the location of our bodies and its parts in the environment (exporprioceptive info)

(the cane is an extension of his body!)

vantage points: rear, frontal, internal, externalIt is harder for us to turn our vantage point than to read through the skull

Disembodies-eye hypothesis: projecting one’s egocenter (aka disembodies eye) to locations in space outside one’s body.

Fifth purpose of perspective: powerful effects can be achieved by creating discrepancies between the natural direction of the viewer’s line of sight and the line of sight implicit in the perspective of the paintingOr by locating the center of projection high above the viewer's eye level. This produces a separation of the mind’s eye with the body's eye which gives a sense of spiritual elevation

Renaissance artists didn’t write about perception much, they focused on intuition. Still, our knowledge isnot that much more advanced than theirs was.

Vs.

A

Chapter 11: The Invention of Perspective and the Evolution of Art

Panofsky & Goodman Gablik

relativists

Why were Romans interested in perspective, not if perspective is truth

Philosophical arguments in support of conception of perspective: Perspective is not an absolute standard of fidelity, it is one of many methods of Representation -depictions=descriptions

Sophogeny recapitulates ontogeny= the Evolution of cultural wisdom parallels the Development of the individual

Thus, perspective drawingMust have rigid rules…

And did and was followedReligiously In the Renaissance

XNothing really….

Refutes Goodman:-Perspective is a geometric system tempered by what perception can and cannot do -There are limits to what our perception can do- we can not arbitrarily change the Way we perceive optical information

Refutes Gablik:They did not follow the rules religiously, geometry was always subordinate to perception

By carefully selecting the dimensions along which comparisons between differentperiods of art were made, you can argue

that one period in art is more advanced than all the others.

Refutes Panofsky: mistaken on some matters- whether or not Perspective is “true” is far less important.

PERSPECTIVE IS “SYMBOLIC FORM” (because of the spiritual elevation that can be experienced)

Ch 11 continued…

Leonardo da Vinci’s “Last Supper”