What about the Gibbon like arms and the misshapen head?
Sorry, but I disagree profoundly with both of those points. It might be best to dispense with detailed reasons - which take time to compose - unless you're genuinely interested in hearing them.
"Metaphor".
(oops...wrong thread)
Well I'm not particularly, but others here certainly will be. Methinks you may have got too close to this subject for too long, and can't actually see the wood for the trees, so to speak. If you cover a human with anything and spread a sheet over them, the ensuing marks on the sheet will not have a mis-sized head, elongated limbs, and banana fingers seen in the image on the shroud.
I accept that you know far more about the chemistry of the shroud than I do. Could you tell us what it is about that chemistry which demonstrates that the images could only have been formed using the flour and oil method you describe? If it isn't the chemistry, what other science might exclude all other explanations? If you can't button it down to a certainty, maybe you might have been a little quick to dismiss my second point.
Very interesting your “washed” hand.Here's a brief reply to the first part of your question, MIkeG. (I may address the other parts later when I've some more time).
There are two possible answers to the 'overlong arms'.
Wait, are you using bleached flour?
Just a polite reminder that you haven't answered this point yet.......I accept that you know far more about the chemistry of the shroud than I do. Could you tell us what it is about that chemistry which demonstrates that the images could only have been formed using the flour and oil method you describe? If it isn't the chemistry, what other science might exclude all other explanations? If you can't button it down to a certainty, maybe you might have been a little quick to dismiss my second point.
Just a polite reminder that you haven't answered this point yet.
Very interesting your “washed” hand.
I think that some alternative hypotheses are possible but they have to explain some features of the body image that are not “natural”. For example:
(1) The fingers are abnormally elongated. The forefinger is longer than the ring finger of the lower hand. This is a classical feature of the late gothic and first Renaisance (Cuatrocento). See this: https://i1.wp.com/upload.wikimedia....d/Duccio_The-Madonna-and-Child-128.jpg?zoom=2
(2) The position of the hands over the pubis is impossible with the angles of the elbows. This elongation of the arms is characteristic of some painters as Boticelli: See his The birth of Venus: http://www.artchive.com/artchive/b/botticelli/venus.jpg
(3) The blood rivulets are naturally impossible whether the person is up or lying. See Garlaschelli demonstration: http://www.aafs.org/sites/default/files/AAFS2014Proceedings.pdf and here: https://www.youtube.com/watch?v=SNzVc1MqJ2s . The blood stains of the back of the head are specially impossible : https://shroudofturinwithoutalltheh...-dorsal-blood-on-hair-cropped.png?w=768&h=411
.
All these unnatural features are visible with naked eye and show that some pictorial retouches are necessary to explain these physical impossibilities.
However, something can be made to discover the real cause of the image only if the church allows that the cloth be examined by an interdisciplinary and independent scientific team. To leave the sindonoligsts be in charge of the investigation is not useless, is harmful. They have no experience of the sophisticated methods of the scientific study of works of art and they are obsessed to demonstrate the authenticity of the Shroud. This is a dangerous mixture.
In addition, the Catholic Church has a big business with the Shroud in Turin. The radiocarbon dating threatened the benefits both spiritual and material and I doubt very much that they risk again.
Sorry, but I don't buy into your idea of acetic acid the generator of the body image's still unidentified chromophore?
It's not the task of science to come up with explanations that exclude all other ones, least of all future ones. One is usually content to account for all KNOWN data without presuming to exclude next year's or next century's data that are not yet in one's possession.
Why do you say "unidentified"? Walter McCrone identified the chromophore particles taken from the STURP tape samples as red ochre and vermillion pigment, consistent with medieval artist's pigments. Based references you've made, I assume you're familiar with McCrone's analysis.
Yup, indeed I am, as perforce must anyone who wishes to be taken seriously as a Shroud researcher. It would take too long to relate all the contrary evidence to McCrone's bizarre claims, though John Heller's book, relating his and Alan Adler's deep scepticism re the origin of traces of red ochre is a good start. (Reminder: the ochre - iron oxide- was too pure to have been derived from an artist's paint pigment and other origins were suggested, like having been adsorbed onto the linen from the natural waters in the flax-retting pond via ion exchange etc etc.)
From my ignorance of the scientific theories of Adler and Heller, I don't attach too much importance of their claims because they didn't present them in an acceptable scientific form in some cases and they seem inconclusive in other. For example: they never quantified their conclusions about the "small" quantity of red particles in the image. McCrone did it. For example: they allegued (Adler) to have produced reddish colour by mixing bilirubin and blood but never presented his experiences. They claimed that there was not any image under the blood stains, but demanded more samples "to confirm" this point. Not very consistent.
I don't know the chemical "performances" of the Maillard reaction neither. But I am certain that the Shroud image was not formed by contact or emanation. The famous vaporografic hypothesis is impossible.
And, as I have said in a previous comment, I consider almost impossible that some features of the image have been produced without human intervention (a painter almost certainly).
I have experimented with varying concentrations of sulphuric acid, but find that the discolouration it produces is very grey, rather than the scorched appearance of the Shroud. I tried vinegar on a whim, and it does produce the correct colour, but only after heating. However I don't believe the image was painted in invisible ink, which is why I have combined it with iron oxide. As David Mo suggests, however, the amount of iron oxide, and in particular whether there is enough to produce an image, and how uniformly distributed it is across the cloth, is inadequately evidenced to be sure about. It is quite difficult to carry out experiments to place, say 1ug of powder evenly over 1cm2 of cloth, so as to observe the visibility of the outcome.
Sorry, I missed Meccanoman's last comment. I have spent some happy hours smearing my face with cocoa and pressing cloths to it, but have never achieved anything remotely satisfactory. There is not only the 'Agamemnon Mask' effect, but also the serious problem of creases and wrinkles, which invariably result in big triangles of non-contacted cloth. Hands, as we can see, are much flatter than faces, so these 'wrapping' distortions are minimised, but I cannot see that technique applying to whole bodies.
The trouble with McCrone is that he was - to put it baldly - a one-trick pony, relying almost entirely on what he could see down his microscope, which gave undue emphasis to traces of particulate material - hardly ideal when dealing with the origins of a diffuse yellow-brown coloration that is more akin to a stain than to an encrustation of artists' paint, ancient or otherwise.