John P. Jackson, Is the image on the Shroud due to a process heretofore unknown to modern science?, Shroud Spectrum International, no. 34, March 1990.

That paper written by a well known Shroud researcher (he was the technical director of the STURP group which in 1978 made an extensive study of the Shroud) presents the hypothesis that the Shroud image formed when the body dematerialized. This hypothesis is based on three inferences, at least two of which appear contradictory if we assume that the Shroud was not forcefully constrained (e.g. flattened) during image formation. This review concludes that one of the apparent contradiction is not compelling: there are observations supporting a unique Shroud configuration when the blood stains and the image formed. The details of the review follow.

In Section II.A of Jackson's paper, three inferences, based on numerous considerations too long to summarize here, are made:

1. The body and blood images were formed directly from a human body that was enveloped in the Shroud.
2. Gravity was a significant factor in the production of the image.
3. The Shroud was in two different draping configurations when the body and blood images were formed.

Notice that inference 3 appears in contradiction with inference 1 if we assume that no external force (e.g. a person flattening the Shroud) occurred. Based on this apparent contradiction, Jackson proposed the hypothesis that the Shroud flattened by itself, by its own weight, when the body dematerialized. That is, the Shroud collapsed -- going through the body -- when the body dematerialized: this is the "Cloth Collapse Hypothesis". This reasoning is presented in Section II.B of his paper.

Interestingly, Jackson -- who wrote his paper in 1990 -- made a prediction from the Cloth Collapse Hypothesis that appeared to have been confirmed by a paper published in 2004 by Fanti and Maggiolo (see reviews): a fainter image than the front appear on the reverse side of the Shroud. But the conclusion of that paper has been challenged -- see a review of this paper in this section.

I think that the major problem with this reasoning is inference 3: that the Shroud should be in two different draping configurations to form the blood stains and the image. This aspect has been studied in a paper I published at the 2005 Dallas Conference -- it is available here. That paper concludes that it is most likely that the Shroud was not flattened between the formation of the blood stains and the image. There are many details to support this conclusion; one that is easily verifiable is the lack of any vertical misregister: no flattening could have occurred since vertical misalignment would otherwise have occurred, which is not perceivable anywhere on the Shroud.

I conclude that the Cloth Collapse Hypothesis tries to solve an apparent contradiction which does not appear to even exist. The fact that the Shroud, draping a real body, would not have moved at all, and yet not create any obvious visible image distortion is at first a counter-intuitive and non obvious fact. But, this fact is a reproducible experiment with cameras and more precisely with a 3D scanner. On the other hand, the Cloth Collapse Hypothesis appears not reproducible. I think then, that this hypothesis will remain an hypothesis, but that the proof that inference 3 is not compelling has already (partly) been shown feasible in Latendresse 2005. But more precise measurements and experiments should be done to give a definitive answer to these results.