Why the Shroud of Turin is not a Fake Relic
Like a playful Georges Seurat painting, the images on the
Shroud emerge from discrete little bits of color in all the right places on
the cloth. But unlike a cheerful and colorful Seurat, there is only one color
in the Shroud's images. It is a single shade of caramel yellow. And unlike
Seurat's pointillism, the bits of color are microscopically tiny. When we
look at the Shroud, what we perceive as different shades of yellow is mere
visual blending. Where there are more or larger bits of yellow the image
appears darker. Where there is less yellow, the image appears lighter.
Pixels, a word that means picture elements, is one way to describe the bits
of color. The image on the Shroud is like a halftone photograph printed in a
newspaper or a grayscale photograph printed in microscopic-size droplets of
black ink on an ink-jet printer.
Very much unlike a Seurat, the image was not painted. Many tests including
visible, ultraviolet and infrared light spectrometry, x-ray fluorescence
spectrometry, and direct microscopic viewing of the Shroud confirm that the
images were not painted despite the fact that Walter McCrone, a noted
microscopic analyst found iron oxide and mercuric sulfide, both used in paint
pigments.
Nowhere on the Shroud are there sufficient concentrations
of paints or dyes to form a visible image. Iron oxide might have formed by
retting flax in iron rich water in the production of linen. And just as one
finds minuscule particles of iron oxide (rust) in airborne dust, so too might
mercuric sulphide be present in dust that settled on the Shroud, once kept in
churches and cathedrals with frescoed walls and ceilings. There is another
possibility that might well explain the presence of trace amounts of paint
particles on the Shroud. Many painted copies of the Shroud were produced. It
was, after all, a revered relic. We know from history of a practice whereby
artists would touch or rub their paintings on the Shroud for sanctification.
Chemists now know the coloration for the images is superficial at the topmost
fiber surfaces of the cloth. The fibers are coated with a thin film of
impurities made up mostly of starch. It is in this coating that the image
resides. The visible image is the result of a chemical change, in certain
places, that results in an observable change of color.
The coating can be physically removed from the fibers with adhesive tape. In fact, flakes of color can be seen where it separated from the fiber and stuck to tape used to collect particulate samples from the Shroud. You can see the thin coat of color through a microscope and it is hard to imagine how an artist could have accomplished this.
The images on the Shroud look ghostlike. They look scorched into the cloth. But chemically they don't resemble scorches. They don't contain the chemical byproducts produced by scorching.
It's possible to imagine that this appearance is what a
crafter of fake relics wanted to create; perhaps to portray some imagined
idea of what the Resurrection was like. But the reason they look ghostlike is
that they are continuous tone negative images. When photographed, the
negative of what is already a negative become the extraordinarily
photographic like image we commonly see. Could the image on the Shroud, in
fact, be a photograph?
Near the end of the fifteenth century, about 130 years after the Shroud's
first public exhibition in Europe, Leonardo da Vinci described a camera
obscura (a pinhole camera) in his notebooks. Aristotle (384-322 BCE)
understood the principle and so did a tenth century Arabian scholar, Alhazen
of Basra, who used a tent-sized camera obscura for observing the cosmos. In
Alhazen's tent images were projected onto a wall where they could be traced
or copied by hand. It wasn't until 1727 when Johann Heinrich Schulze
discovered that silver mixed with nitric acid created a photosensitive
compound that turned dark when exposed to light. And, it wasn't until 1816
when Nicéphore Niépce used a camera obscura with a sensitized paper to create
an image. In 1834, Henry Fox Talbot created the first stable photographic
negative on paper soaked in silver chloride.
Had someone, perhaps, invented photography several
centuries earlier even though there is no written evidence or samples of
photographic experiments or works? Is the Shroud the work of a scientific
genius whose accomplishments are lost to history? While some people have
opined that it might be, there is ample evidence the Shroud is not a
photograph.
When we look at the Shroud we see what looks like a picture. What to our eyes
seems like the highlights, lowlights, and cast shadows of reflected light on
a human form is not light at all. It is certainly not light as a camera would
detect it or an artist would see it and translate it to canvas. Technical
image analysis reveals no directionality to the implied light of the
highlights and shadows. The brightness does not come from any angle. It is
not from above or below, nor from the right or the left, nor from the front.
Furthermore, if the image was produced using photosensitive materials, the
gradations of brightness would produce different shades of color, not
discrete densities of pixels.
So what does the tonality of the image—made
up of pixels—represent if not reflected light? With
computer software we can plot the relative lighter and darker areas seen in
the images and produce a three-dimensional isometric drawing of the body.
With computerized virtual reality we can view the body from different angles.
We can see the slope of the nose, the recesses of the eye sockets and the
shape of the torso. It seems that the image is a graphic representation
of the distance between any part of the body and the cloth. This is
startling. You cannot do this with a regular photograph or a painting or any
known type of pictorial art. There is nothing at all like this imagery in the
history of art.
In 1898, an amateur photographer, Secondo Pia, photographed the Shroud for
the first time in history. On his glass plate negative (Talbot's invention)
an extraordinarily positive image likeness of a man emerged. Pia's negative
of a negative revealed the details of the ghost-like images. But the image is
not really a negative. It just happens, serendipitously, to act like one. It
is a topographic datagram in microscopic, monotonal pixels. However the image
was formed, it was recorded chemically. The privilege of modern technology
lets us see that it looks like a painting or a photograph of a naked man
crucified with nails through his wrists. This same modern technology tells us
it is not a painting or a photograph.
Despite many attempts to do so, no one has found or invented an artistic or
crafty technique that can reproduce even a few of the characteristics of the
images. But that does not mean, that in the future, someone will not find a
method to create such images. But if someone does so, a tenacious question
will remain:
How likely is it that there would be such a one-of-a-kind work of art for which there are no known precedents; created by methods that were never again exploited?
Any method that might be devised must be scientifically
credulous, fit into the history of art and conform to the cultural
expectations in which the technology was supposedly employed. If not, it will
be seen as newly invented art designed to mimic an otherwise unexplained
natural process or a supernatural event. The skeptic has a dilemma. To
believe that the Shroud is fakery he or she must rely on an underlying belief
that transcends scientific fact.
John A. T. Robinson, always creatively challenging conventional wisdom about
New Testament interpretations and provenance, doubted that the Shroud was the
work of a forger. On the basis of what would have been medieval understanding
of scripture, he argued: "This . . . is not, I suggest, how any forger would
have thought. He would have imagined it [=the sudarion, the other cloth,
understood to be a face cloth] lying over the face, rather like the bogus St.
Veronica's handkerchief, and incorporated its image on a separate piece of
material."
Home Page & Introduction: The Shroud of Turin Story - A Guide to the Facts 2005
© 2004 Daniel R. Porter, Bronxville, New York
