What is right or wrong with this material from page 9 of The Shroud: A Critical Summary of Observations, Data and Hypotheses, by Robert W. Siefker and Daniel S. Spicer.
Table I, Item 2.0:
The body image has the normal tones of light and dark reversed, so the body parts nearer the cloth are darker. This fact leads us to state that the body image appears as a photographic negative. See the contrasting naked eye and photographic negative images of the face below.
Naked Eye View Photo Negative
Italian photographer Secondo Pia took the first official photographs of the Shroud in 1898. He had been invited to photograph the Shroud while it was being exhibited to the public in the Turin Cathedral. As he developed the film he was shocked to see what was revealed. His negatives showed incredibly detailed images of an anatomically correct, naked and crucified man, which could simply not be seen when viewing the Shroud with the naked eye. When released to the public, Pia’s photographic negative images acted to spontaneously launch modern scientific forensic and historical inquiry into the Shroud. As a result the Shroud has arguably become the single most studied artifact in history.
Hugh Farey questions the wording in a comment to another posting about this paper:
The normal tones are reversed. The normal tones of what? Of body parts? I’m not light on the nose and dark in the cheeks.
Well said, Hugh. I agree.
Actually, these almost identical words appear in “Evidences for Testing Hypotheses About the Body Image Formation of the Turin Shroud” published by the Shroud Science Group. It is signed by twenty four people, including me. I now have some regrets about having signed it, but only because I have thought it through some more. When Giulio Fanti tried to present this paper at the Third Dallas International Conference on the Shroud of Turin, September 8-11, 2005, organizers sought to block it. I did find an alternate venue and Fanti was able to present the paper to most of the attendees. I would do that again even if I wouldn’t sign it again. Anyway, here is the wording:
B27) The body image has the normal tones of light and dark reversed with respect to a photograph, such that parts nearer to the cloth are darker (Jumper 1984, Craig 2004, Schneider 2004).
Why not simple say that it seems to be like or act like a photographic negative? But I know, even that seems imprecise.
My real objection to this statement is how much it implies under the guise of being an objective “established” observation. Really, “so the body parts nearer the cloth are darker,”? Nearer? How is that observed? Could we say if we imagine that a cloth covers a body?
I can’t say the comment is wrong. In the end it seems almost obviously correct. But it is not observed.