Secundo Pia took the first photograph of the Shroud.
On the photographic negative, he was able to observe a
positive image of the man in the Shroud.
A negative is a
positive, thus the real photographic negative shows a
"optic positive" of the man of the Shroud.
analysis points to the possibility that the image, no
matter how it was formed, was produced by a real body.
of the most striking characteristic of the image is
that it encodes three-dimensional information,
something that can not be found in paintings or
photographs. When processing the image with
an image analyzer, we can extract three-dimensional
information, (anyone can do it with the appropriate
computer software) it shows a human body in 3-D. The
body parts that were closer to the cloth can been seen
in relief from the parts more distant to it. The
intensity of the image is inversely proportionate to
the body-cloth distance in each point: the image is
darker (lighter in the negative) in those areas where
the distance body-cloth was smaller. This rule is
mathematically true for the entire image, and it has
been calculated that the distance between the body and
the cloth could not have been more than 3.5 cm. From
this analysis it can be easily concluded that
the image was not a
result of direct contact between body and cloth, such
that we would only have the image of the body parts
directly in contact with the Shroud.