What is right or wrong with this material from The Shroud: A Critical Summary of Observations, Data and Hypotheses, by Robert W. Siefker and Daniel S. Spicer.
Table I, Item 5.1:
Compared to the frontal image, there is no double superficiality of the dorsal or back image.
An image formation hypothesis that is able to account for a frontal double superficiality of the face must also be consistent with there being no dorsal double superficiality..
Really? Can we say this? Do we know? We can barely see some image on the reverse side of the cloth for the ventral image. How do we know it wasn’t there for the dorsal image, only too faint to see with the methods used? Is it like saying at mid-morning that there are no stars in the sky? Might we say, “I think I don’t see.”