Wednesday, June 24, 2015

15th C Linear Perspective Masaccio and Mantegna




Perspective Webster's dictionary defines "perspective" in a variety of ways:
2 a: the interrelation in which a subject or its parts are mentally viewed ; also: point of view b: the capacity to view things in their true relations or relative importance
So perspective is really just a point of view.  This section will deal with a variety of points of view.  Visual systems such a linear perspective will be discussed as well theological, humanistic and neoplatonic points of view.
 

Cimabue, Madonna Enthroned c1280
Late Gothic Italian 

space,  picture plane, and overlapping
Paintings on a flat two dimensional space employ different ways of creating space.  Before the Renaissance period artists looked at a picture as a kind of window.  The front of this window is sometimes referred to as the picture plane.  As you look through the front of the plane, like a window, you will see things that are in the foreground or front of the picture, then in the middle ground, and finally the background.  In this painting in particular, this artist, named Cimabue, is trying to create the illusion of space by layering or overlapping one figure in front of another, however, you can see that he really does not create the illusion of space or deep space too convincingly.


Giotto, St Francis Giving his Mantle to a Poor Man, c1305
Late Gothic sometimes his style is considered 
Proto Renaissance or Early Renaissance
Giotto, a student of Cimabue, is one of the first Italian artists to really try to create some sort of space in the picture plane.  If you look at this painting you can see that he has claerly created a foreground, where the men and the donkey are, a mid-ground, where the mountains start to rise, and then a background where the buildings are.  He creates this illusion in several ways.  One way is that he overlaps or layers the figures.  The other is that he uses dimunution.  Things in the background diminish, or get smaller.  Giotto creates space is that he changes the size of things as they move back in space.  The buildings and mountains are much smaller than the people are in the foreground.  This difference in size is refered to as a size scale relationship
The building in this image and the others like it are rendered with the illusion of space called intuitive perspective and isometric perspective.  (This kind of perspective is not as illusionistic as the linear perspective that is invented during the Renaissance around 1400 CE.)

Different artists and different cultures through out time have tried their hand at creating the illusion of space or realism in their art.
 

 


Fowling Scene from the tomb of Nebamun
1400 BCE - 1350 BCE
Thebes, Egypt
Dynasty 18
According to the Brittanica: Perspective is a method of graphically depicting three-dimensional objects and spatial relationships on a two-dimensional plane or on a plane that is shallower than the original (for example, in flat relief).
Perceptual methods of representing space and volume, which render them as seen at a particular time and from a fixed position and are characteristic of Chinese and most Western painting since the Renaissance, are in contrast to conceptual methods. Pictures drawn by young children and primitives (untrained artists), many paintings of cultures such as ancient Egypt and Crete, India, Islam, and pre-Renaissance Europe, as well as the paintings of many modern artists, depict objects and surroundings independently of one another--as they are known to be, rather than as they are seen to be--and from the directions that best present their most characteristic features. Many Egyptian and Cretan paintings and drawings, for example, show the head and legs of a figure in profile, while the eye and torso are shown frontally . This system produces not the illusion of depth but the sense that objects and their surroundings have been compressed within a shallow space behind the picture plane.


Leonardo da Vinci, Last Supper, 1495-7 Milan, 
Santa Maria delle Grazie 
According to the Brittanica:
In Western art, illusions of perceptual volume and space are generally created by use of the linear perspective system, based on the observations that objects appear to the eye to shrink and parallel lines and planes to converge to infinitely distant vanishing points as they recede in space from the viewer. Parallel lines in spatial recession will appear to converge on a single vanishing point, called one-point perspective. Perceptual space and volume may be simulated on the picture plane by variations on this basic principle, differing according to the number and location of the vanishing points. Instead of one-point (or central) perspective, the artist may use, for instance, angular (or oblique) perspective, which employs two vanishing points.

Linear perspective is a mathematical system for creating the illusion of space and distance on a flat surface. The system originated in Florence, Italy in the early 1400s. The artist and architect Brunelleschi demonstrated its principles, but another architect and writer, Leon Battista Alberti was first to write down rules of linear perspective for artists to follow. Leonardo da Vinci probably learned Alberti's system while serving as an apprentice to the artist Verrocchio in Florence. To use linear perspective an artist must first imagine the picture surface as an "open window" through which to see the painted world. Straight lines are then drawn on the canvas to represent the horizon and "visual rays" connecting the viewer's eye to a point in the distance.
The horizon line runs across the canvas at the eye level of the viewer. The horizon line is where the sky appears to meet the ground.
The vanishing point should be located near the center of the horizon line. The vanishing point is where all parallel lines (orthogonals) that run towards the horizon line appear to come together like train tracks in the distance.
Orthogonal lines are "visual rays" helping the viewer's eye to connect points around the edges of the canvas to the vanishing point. An artist uses them to align the edges of walls and paving stones.
Please visit this site for more of an explanation.
http://psych.hanover.edu/Krantz/art/linear.html

 


Masaccio, Trinity with Donors, c1425 - 8?
fresco in the 
Church of Santa Maria Novella, Florence
21'x10'5"
According to the Brittanica:
The early European artist used a perspective that was an individual interpretation of what he saw rather than a fixed mechanical method. At the beginning of the Italian Renaissance, early in the 15th century, the mathematical laws of perspective were discovered by the architect Filippo Brunelleschi, who worked out some of the basic principles, including the concept of the vanishing point, which had been known to the Greeks and Romans but had been lost. These principles were applied in painting by Masaccio (as in his "Trinity" fresco in Santa Maria Novella, Florence; c. 1427), who within a short period brought about an entirely new approach in painting. A style was soon developed using configurations of architectural exteriors and interiors as the background for religious paintings, which thereby acquired the illusion of great spatial depth. In his seminal Della pittura (1436; On Painting), Leon Battista Alberti codified, especially for painters, much of the practical work on the subject that had been carried out by earlier artists; he formulated, for example, the idea that "vision makes a triangle, and from this it is clear that a very distant quantity seems no larger than a point." Linear perspective dominated Western painting until the end of the 19th century, when Paul Cézanne flattened the conventional Renaissance picture space. The Cubists and other 20th-century painters abandoned the depiction of three-dimensional space altogether and hence had no need for linear perspective.
Linear perspective plays an important part in presentations of ideas for works by architects, engineers, landscape architects, and industrial designers, furnishing an opportunity to view the finished product before it is begun. Differing in principle from linear perspective and used by both Chinese and European painters, aerial perspective is a method of creating the illusion of depth by a modulation of color and tone. 

 

Dennis Hwang, a student from Stanford was so taken with the three dimensional quality of the image that he designed a virtual reality image that simulates another view of Masaccio's fresco. http://graphics.stanford.edu/courses/cs99d-98/online_projects.html

 



Masaccio, Trinity with Donors, c1425 - 8?
fresco in the Church of Santa Maria Novella, Florence
21'x10'5"
Form: This is a tremendous work of art.  The figures in the work are just slightly bigger than life size.  The overall composition of the works is symmetrical and the composition within the arch is based on a stable pyramidal form.  While not strictly in accordance with the rules of perspective, this form is a visual device that draws the eye back into the picture plane. The figures of God the Father, The Spirit (which is a Dove that doubles for God's collar) and the crucified Jesus are placed with a Roman triumphal arch complete with Pantheon like coffers and ionic columns on the edges.  Moving out of the arch on either side are two flattened pilasters (squared off half columns) that have corinthian capitals.
The work is executed in one point perspective with the horizon line placed right on the level of the first trompe l’oeil ledge at the viewer's eye level.   The figures representing the two donors or patrons are located on a ledge about six feet off the ground, just outside of the arch slightly above the viewer's point of view. Beneath the ledge/horizon line is a painted skeleton representing a tomb.
Iconography:  Symbolically speaking this image is packed with all kinds of different perspectives. 
The linear perspective is both a formal device, which creates space, and a way of including the viewer.  The fact that the use of linear perspective is used actually symbolizes that the real subject of the painting is not the Trinity but rather the Renaissance man's relationship to it.  This leads us to discuss the various themes that are hidden within the obvious meaning behind the fresco.
It's almost a shopping list of ideas. 
idealism
neoplatonism
humanism
theology
Overall, the fresco does represent a theological (religious) point of view.  More specifically it represents a unification of the Trinity as expressed in the Catholic Nicene Creed.
We believe in one God, the Father Almighty, maker of all things visible and invisible; and in one Lord Jesus Christ, the Son of God, the only-begotten of his Father, of the substance of the Father, God of God, Light of Light, very God of very God, begotten, not made, being of one substance with the Father.
The Brittanica refers to Masaccio's Trinity as "rational, human-scaled and human-centred, and inspired by the ancient world."  This statement illustrates that beyond a theological point of view, the naturalistic life-size scale and placement of the figures of God the Father, The Spirit, within a Roman triumphal arch complete with Pantheon like coffers and ionic columns on the edges, represents how the Renaissance person was framing their view of the world within a classicizing and humanistic point of view.  Jesus' body is idealized and he looks almost as if he is a Greek god.  God the Father looks like a Greek or Roman philosopher and these representations make reference to the new ideas concerning neoplatonism and humanism. The neoplatonic aspect, deals with the concept of humankind's ability to be perfected to an ideal state.  One that is more spiritual and mental than flesh.  The humanistic point of view deals with the concept that while humankind is spiritual it is also physical and emotional.  When the body of Christ is depicted as a real human's body, the artist is showing you a point of view based on a more human and possibly even fallible point of view of the world.  The perfectibility of man and the ideal conception of a what a perfect person should be is discussed in Mencher, Liaisons 109-112 Baldassare Castiglione (1478-1529) Il Cortegiano (The Courtier) Excerpts from "The First Book of the Courtier"  and William Shakespeare c1600 excerpts from Hamlet 115-117All of these points of view are pulled together in by the appearance and text above the skeleton.
Above the skeleton is inscribed, "What I was you are.  What I am, you will become."  This idea that we are to be reminded of our mortality and frailty is a reminder or a lesson referred to as a memento mori.  A literal reminder of death.  This them is taken up not just in the visual arts but also in literature and theatrical productions.  Read Mencher, Liaisons, William Shakespeare c1600 excerpts from Hamlet115-117 for another example.  What kinds of iconography to they both share?

Masaccio. Tribute Money, and Expulsion, fresco c1427 
Brancacci Chapel, Santa Maria del Carmine Florence, 
Italy, Italian Renaissance

Context: Masaccio. Tribute Money, and Expulsion, fresco c1427  are prime examples of many of the innovations that marked 15th century Italian art.  In addition to demonstrating all of the formal views concerning perspective, these frescoes also express all of the more philosophical points of view.
According to the Brittanica: 
The Brancacci Chapel. Shortly after completing the Pisa Altarpiece, Masaccio began working on what was to be his masterpiece--the frescoes of the Brancacci Chapel (c. 1427) in the Florentine Church of Santa Maria del Carmine. He was commissioned to finish painting the chapel's scenes of the stories of St. Peter after Masolino (1383-1447) had abandoned the job, leaving only the vaults and several frescoes in the upper registers finished. Previously, Masaccio and Masolino were engaged in some sort of loose working relationship. They had already collaborated on a "Madonna and Child with St. Anne" (Uffizi Gallery, Florence) in which the style of Masaccio, who was the younger of the two, had a profound influence on that of Masolino. It has been suggested, but never proven, that both artists were jointly commissioned to paint the Brancacci Chapel. The question of which painter executed which frescoes in the chapel posed one of the most discussed artistic problems of the 19th and 20th centuries. It is now generally thought that Masaccio was responsible for the following sections: the "Expulsion of Adam and Eve" (or "Expulsion from Paradise"), "Baptism of the Neophytes," "The Tribute Money," "St. Peter Enthroned," "St. Peter Healing the Sick with His Shadow," "St. Peter Distributing Alms," and part of the "Resurrection of the Son of Theophilus." (A cleaning and restoration of the Brancacci Chapel frescoes in 1985-89 removed centuries of accumulated grime and revealed the frescoes' vivid original colours.)
There are other forms of perspective and one of them, which is slightly later development used by Masaccio but perfected by Leonardo is called aerial perspective.  According to the Brittanica,
 



Masaccio. Tribute Money, and Expulsion, fresco c1427 
Brancacci Chapel, Santa Maria del Carmine Florence, Italy, Italian Renaissance

Photo of atmospheric perspective 
Aerial perspective also called ATMOSPHERIC PERSPECTIVE, method of creating the illusion of depth, or recession, in a painting or drawing by modulating color to simulate changes effected by the atmosphere on the colours of things seen at a distance. Although the use of aerial perspective has been known since antiquity, Leonardo da Vinci first used the term aerial perspective in his Treatise on Painting, in which he wrote: "Colours become weaker in proportion to their distance from the person who is looking at them." It was later discovered that the presence in the atmosphere of moisture and of tiny particles of dust and similar material causes a scattering of light as it passes through them, the degree of scattering being dependent on the wavelength, which corresponds to the color, of the light. Because light of short wavelength--blue light--is scattered most, the colours of all distant dark objects tend toward blue; for example, distant mountains have a bluish cast. Light of long wavelength--red light--is scattered least; thus, distant bright objects appear redder because some of the blue is scattered and lost from the light by which they are seen. The intervening atmosphere between a viewer and, for example, distant mountains, creates other visual effects that can be mimicked by landscape painters. The atmosphere causes distant forms to have less distinct edges and outlines than forms near the viewer, and interior detail is similarly softened or blurred. Distant objects appear somewhat lighter than objects of similar tone lying closer at hand, and in general contrasts between light and shade appear less extreme at great distances. All these effects are more apparent at the base of a mountain than at its peak, since the density of the intervening atmosphere is greater at lower elevations.
 "aerial perspective."   Britannica 2001 Standard Edition CD-ROM.   Copyright © 1994-2001 Britannica.com Inc.   November 19, 2002. 

 



chiaroscuro
 
The picture plane is further unified by its value structure or shading.  This use of light and shadow to create a dramatic and consistent picture plane is  referred to as chiaroscuro. According to the Brittanica, 
 

Chiaroscuro (from Italian chiaro, "light"; scuro, "dark"),
technique employed in the visual arts to represent light and shadow as they define three-dimensional objects.
Some evidence exists that ancient Greek and Roman artists used chiaroscuro effects, but in European painting the technique was first brought to its full potential by Leonardo da Vinci in the late 15th century in such paintings as his "Adoration of the Magi" (1481; Uffizi, Florence). Thereafter, chiaroscuro became a primary technique for many painters, and by the late 17th century the term was routinely used to describe any painting, drawing, or print that depends for its effect on an extensive gradation of light and darkness.
The scene depicted in "The Tribute Money" is consistently lit from the upper right and thus harmonizes with the actual lighting of the chapel, which comes from a window on the wall to the right of the fresco. The mountain background of the fresco is convincingly rendered using aerial perspective; an illusion of depth is created by successively lightening the tones of the more distant mountains, thereby simulating the changes effected by the atmosphere on the colours of distant objects. In "The Tribute Money," with its solid, anatomically convincing figures set in a clear, controlled space lit by a consistent fall of light, Masaccio decisively broke with the medieval conception of a picture as a world governed by different and arbitrary physical laws. Instead, he embraced the concept of a painting as a window behind which a continuation of the real world is to be found, with the same laws of space, light, form, and perspective that obtain in reality. This concept was to remain the basic idiom of Western painting for the next 450 years. 
 "chiaroscuro."  and "Masaccio"  Britannica 2001 Standard Edition CD-ROM.   Copyright © 1994-2001 Britannica.com Inc.   November 19, 2002. 
 
Although Giotto uses the technique somewhat in his paintings, notice how chiaroscuro is employed by Masaccio in the image on the left to make the figures appear more life like.  Also notice how Masaccio has become so involved with perspective that the halo atop the apostles heads are represented as an elliptical plates floating above rather than the more traditional circle of light that surrounds the heads of Giotto's and Cimabue's figures.
 
Context and Iconography:  In order to really understand this next section you need to know the story of the Tribute Money.  I think that what Masaccio was doing was following the lessons and type of sermons that would have been delivered in Church.  In these sermons, two stories concerning the testing of Jesus might have been combined.
 

Matthew Chapter 17
 

24  When they came to Capernaum, the collectors of the temple tax approached Peter and said, "Doesn't your teacher pay the temple tax?"

25 "Yes," he said. When he came into the house, before he had time to speak, Jesus asked him, "What is your opinion, Simon? From whom do the kings of the earth take tolls or census tax? From their subjects or from foreigners?"

26 When he said, "From foreigners," Jesus said to him, "Then the subjects are exempt.

27 But that we may not offend them, go to the sea, drop in a hook, and take the first fish that comes up. Open its mouth and you will find a coin worth twice the temple tax. Give that to them for me and for you."

Matthew Chapter 22

15  Then the Pharisees went off and plotted how they might entrap him in speech.

16 They sent their disciples to him, with the Herodians, saying, "Teacher, we know that you are a truthful man and that you teach the way of God in accordance with the truth. And you are not concerned with anyone's opinion, for you do not regard a person's status.

17 Tell us, then, what is your opinion: Is it lawful to pay the census tax to Caesar or not?"

18 Knowing their malice, Jesus said, "Why are you testing me, you hypocrites?

19 Show me the coin that pays the census tax." Then they handed him the Roman coin.

20 He said to them, "Whose image is this and whose inscription?"

21 They replied, "Caesar's." At that he said to them, "Then repay to Caesar what belongs to Caesar and to God what belongs to God."

22 When they heard this they were amazed, and leaving him they went away.

Masaccio also uses linear perspective to focus the attention on the viewer to the central figure of Christ.  In addition to this, he also places the heads of the apostles on the horizon line almost as if they were ducks in a shooting gallery. The Tribute Money is a continuous narrative.  Meaning that all the episodes of the story are united in one picture plane, such as we see in Nicola Pisano's Nativity, however in Masaccio's image the space makes more sense.  He also divides the story in three segments by using linear perspective.
The vanishing point also divides the picture plane in two sections.  On the left we see the mountains and natural world depicted almost as an infinite place.  To the right of the picture plane, and on the left hand of Jesus, the place where the damned are traditionally placed are the manmade structures of the city.
What this may represent is a concept that is expressed by the story of the Tribute Money as interpreted by St. Augustine 354-430.  According to the Brittanica, Augustine's, "adaptation of classical thought to Christian teaching created a theological system of great power and lasting influence. His numerous written works, the most important of which are Confessions and City of God, shaped the practice of biblical exegesis and helped lay the foundation for much of medieval and modern Christian thought."
 
St. Augustine, came up with a concept in which he viewed the universe and man's existence as divided in two worlds.  One was the City of Man which was temporary and fallible.  This is represented by the architecture and the place in which the tax collectors stands and collects what is "due Caesar."  The other world is the City of God which goes on forever and in which god will provide for the faithful.  This is where Peter pulls the coin from the fishes mouth. Stokstad points out that this story was also used as a propagandistic tool and a way of instilling patriotism for Florence and raising funds.
o Form:  These two nude figures are depicted in an anatomically accurate manner.  The angel of Michael above escorts them out of a triumphal arch and out into a seemingly featureless landscape.  The bodies are arranged in expressive poses. The torso of the angel floating above has been somewhat foreshortened.

Iconography:  The classical arch symbolizes the figures expulsion from a classical and ideal world: the Garden of Eden.  The expression of there bodies ties in with some of the ideas of human expression that one can see in monuments like the Parthenon's metopes and the Ara Pacis Augustae, except in this case, Masaccio uses the language of gesture to directly communicate what each one of these figures is feeling.  My Professor Broderick, from Lehman college, suggested that the figure of Adam is ashamed of himself in a more internal way and therefore hides his face from us and from God.  In contrast to this, Eve, is more superficially ashamed and hides her body.  For Broderick, this was an expression of male and female roles during the Renaissance.

 
 



Albrecht Durer, Alberti's Veil c1500
One way of dealing with perspective and foreshortening is to use mechanical devices to help the artist figure out how perspective works.  In the central image, Durer is using a device based on a treatise by Alberti.  This device allows the artist to abstract the image and chart the image into a series of squares.  This gives the artist many more reference points and allows him to check and measure the way things are foreshortened.
This machine is based on a device that artists used to make multiple copies of the same image or to enlarge a drawing accurately for placement on a wall or canvas.  This process is called "grid and transfer" or "squaring."  According to the Brittanica,
"Squaring" in painting, simple technique for transferring an image from one surface to another (and sometimes converting the image from one scale to another) by non mechanical means. The original work to be transferred is divided into a given number of squares; the same number of squares is then marked off-- with charcoal or some other easily removable medium--on the surface of the receiving area. The contents of each square of the original are then drawn in the corresponding square of the reproduction. The use of the grid ensures the accurate placement of images onto the reproduction. The Egyptians used squaring at least 5,000 years ago. It has been used to transfer cartoons onto murals, to transfer preparatory drawings onto canvas paintings, and to alter the scale of any work in the same media.
This process was used extensively during the Renaissance.  Check this out:
http://www.clevelandart.org/techniques/squaring.html
also see this
http://www.aliciastrose.com/f-process.html
Two Point Perspective
 


1) To draw a simple shape in two point perspective you start with a single line across the picture plane called the horizon line.
 

3) Next, add converging lines from the top and bottom of the vertical line and draw two vertical lines which will become the back corners of the box.

2 Then add two vanishing points.  Place one at each end of the horizon line. Then draw a vertical line as big as you want the first box.

4) After erasing some of the horizon line (the part behind the box) it looks like a three dimensional form.
 
A page with a great example of two point perspective.
http://www.proviso.k12.il.us/EAST/GeometryWorld/2PER.HTM
 
 


Gustave Caillebotte, Paris a Rainy Day, 1877
French, Impressionism
Here's an example of two point perspective in a painting.  This painting actually has multiple points on the horizon line but I've traced most of the orthagonals to the two most dominant ones in the black and white illustration. Here's how Giotto kind of had it right.

 

Here's where the lines should have gone.

 
 

Giotto di Bondone, Virgin and Child Enthroned, 
(Ognissanti Altar,) c 1310. 
Tempera and gold on wood, 10'8"x6'8"
Galleria degli Uffizi, Florence
Cimabue, Virgin and Child Enthroned, 
from the Church of Santa Trinita, Florence
c 1280. Tempera and gold on wood, 12' 7"x7'4"
Galleria degli Uffizi, Florence


Masaccio, Madonna Enthroned, 1426,
oil on panel, 56x29"
London, National Gallery
These two works of art on the left are ones that you have already studied extensively.  Compare these two works to this one by Masaccio.  Think about and be prepared to relate the concepts you have just learned about to them.
 

Andrea Mantegna,  The Dead Christ, c1490-1501, 
tempera on canvas 20"x31" 
Pinacoteca di Brera, Milan, Italy
Italian Renaissance
Form,  From the left hand side of the image are the two profile views of Mary and St. John who lean over the body of Jesus who is rendered in an idealized and muscular fashion  The shroud which partially covers the lower part of the body accentuates the form of the anatomy beneath the drapery.
The most striking aspect of this image is the fact that the portrayal of Christ from a radical point of view.  This view is called foreshortening which you have already encountered in Giotto's Lamentation.   According to the Brittanica, foreshortening is a, 
method of rendering a specific object or figure in a picture in depth. The artist records, in varying degrees, the distortion that is seen by the eye when an object or figure is viewed at a distance or at an unusual angle. In a photograph of a recumbent figure, for instance, those parts of it, such as the feet, that are nearest the lens will seem unnaturally large, those at a distance, such as the head, unnaturally small. The artist may either record this effect exactly, producing a startling illusion of reality that seems to violate the picture plane (surface of the picture), or modify it, slightly reducing the relative size of the nearer part of the object, so as to make a less aggressive assault on the viewer's eye and to relate the foreshortened object more harmoniously to the rest of the picture. Insofar as foreshortening is basically concerned with the persuasive projection of a form in an illusionistic way, it is a type of perspective, but the term foreshortening is almost invariably used in relation to a single object, or part of an object, rather than to a scene or group of objects.

Iconography:  The muscular and idealized quality of the figure probably relates back to the new humanistic and neoplatonic concepts now being used by the REnaissance artists.  Here Mantegna is getting you to identify with the more human qualities of the earthly or corporal body of Christ. 

In fact, the draper reveals how fully human he is.  To paraphrase the ideas from The Sexuality of Christ in Renaissance Art and in Modern Oblivion, by Leo Steinberg, images of Jesus which accentuate how earthly nature, notice how the genitals are somewhat highlighted by the drapery, are an attempt to show the dual nature of Jesus.  Jesus was both of the flesh and spirit and the depiction of his ability to function fully as a carnal being is an attempt to demonstrate that Jesus made a choice to follow a more fully Platonic or ideal path.
Even though the figure is foreshortened, there is a bit of a problem in how the foreshortening is portrayed.  If you compare the foreshortening in Mantegna's work to the drawing below, you may notice that the feet are a bit too small in Mantegna's work and this appears to be done on purpose.    Why do you think this is so?  What purpose do you think it might serve? 
According to this site (I'm not sure how accurate it is but it sure is a great idea), http://www.sindone.org/en/icono/mantegna.htm
The body of Christ is partially covered by the shroud, it lays on a reddish stone with light white veins. (the anointing rock). . . Although this rock is never mentioned in the gospels, it appears in  Costantinopolis as a passion relic in about 1170. The description which coincides with the painting of Mantegna was transmitted in reports made by pilgrims.  It was believed it came from Ephesus (Mary of Magdala took it there from Jerusalem) and the white veins were produced by the tears of Our Lady weeping next to the body of her dead son.
The boldness of the view makes the scene more dramatic; the vision from the top to the bottom and from the depth gives prominence to the nail open wounds which are no longer bleeding. The flesh beneath the torn skin is depicted by the precision of an anatomist.  On the left there are some characters: Mary is weeping, John is praying and Mary of Magdala perhaps is sorrowful. On the right there is a small flask of ointment and an opening towards a dark room: both signs of the imminent burial.
 

hu.man.ism n (1832) 1 a: devotion to the humanities: literary culture b: the revival of classical letters, individualistic and critical spirit, and emphasis on secular concerns characteristic of the Renaissance 2: humanitarianism 3: a doctrine, attitude, or way of life centered on human interests or values; esp: a philosophy that usu. rejects supernaturalism and stresses an individual's dignity and worth and capacity for self-realization through reason -- hu.man.ist n or adj -- hu.man.is.tic adj -- hu.man.is.ti.cal.ly adv me.men.to mo.ri n, pl memento mori [L, remember that you must die] (1596): a reminder of mortality; esp: death's-head
me.men.to n, pl -tos or -toes [ME, fr. L, remember, imper. of meminisse to remember; akin to L ment-, mens mind--more at mind] (1580): something that serves to warn or remind; also: souvenir

Neo.pla.to.nism n (1845) 1: Platonism modified in later antiquity to accord with Aristotelian, post-Aristotelian, and oriental conceptions that conceives of the world as an emanation from an ultimate indivisible being with whom the soul is capable of being reunited in trance or ecstasy 2: a doctrine similar to ancient Neoplatonism -- Neo.pla.ton.ic adj -- Neo.pla.to.nist n
trompe l’oeil - (French: "deceive the eye"), in painting, the representation of an object with such verisimilitude as to deceive the viewer concerning the material reality of the object. This idea appealed to the ancient Greeks who were newly emancipated from the conventional stylizations of earlier art. Zeuxis, for example, reportedly painted such realistic grapes that birds tried to eat them. The technique was also popular with Roman muralists. Although trompe l’oeil never achieved the status of a major artistic aim, from the early Renaissance on, European painters occasionally fostered illusionism by painting false frames out of which the contents of a still life or portrait appeared to spill, or by creating window-like images suggesting actual openings in the wall or ceiling. (Brittanica)
Value Structure
Is the lightness or darkness of a color or shade.  Chiaroscuro and tenebrism both employ the use quick shifts of light and dark.
Value refers to the lightness or darkness of a color. It is a variable that can substantially alter a color's appearance, and as we will see later, it is also an important factor in achieving legibility with type and color. A hue changes in value when either white or black are added to it. A color with added white is called a tint (fig.7) ; a color with added black is called a shade (fig.8). Generally speaking, pure hues that are normally light in value (yellow, orange, green) make the best tints, white pure hues that are normally dark in value (red, blue, violet) make the most desirable shades. The palettes colors below shoes a spectrum of tints and shades based on the hues from the colors clearly shows that changes in value greatly expand color possibilities.
 
 


fig.7

fig.8