Showing posts with label contact imprint. Show all posts
Showing posts with label contact imprint. Show all posts

Wednesday, June 24, 2015

That Man on the Turin Shroud: the mystery may finally be solved - at least in principle - plus that Taiwan water park fireball horror.


I say we're nearly there


Let's stop beating about the bush shall we ? The image of the man on the Turin Shroud is an imprint (not a painting as Charles Freeman would have us believe), I repeat,  an IMPRINT. It's a contact imprint, to be more precise (no physical contact, no image).  This blogger/retired scientist has previously enumerated at least 15 reasons why the TS image an imprint, and does not need to repeat them here.(But since they are buried in the tail end of a previous posting, I shall be listing them here later as an appendix).

This posting focuses on just one feature of the Shroud image which is consistent with the view that the image is a contact imprint. I then make what some will see as a bald assertion, namely that if it's possible to reproduce the 'look' of that image, with its imprint features, then it almost certainly IS an imprint.

The onus would then be on others who think otherwise, who have their own hypotheses, or as often or not fantasies as to how the image was produced, to do what I (with some assistance from my wife)  have done this morning, namely to model their ideas experimentally. If they cannot, or will not do that, then their ideas are unscientific, and need  detain this scientist no further.

Here's the selected feature of interest - the crossed hands. Here's how they appear on the Shroud.

Shroud Scope image (Durante 2002) no further enhancement
As above, with my standard photo-enhancement settings (-7,100,15 brightness/contrast/midtone values in MS Office Picture Manager.
  

Why do I say that's a contact imprint? Answer: the spindly fingers (see previous modelling with a tacky paint-like substance) and the pale area immediately below the upper hand where the linen has bridged, leaving a non-contact air gap.

Can it be modelled?

Answer: yes. approximately, what you see here being the second attempt using the more controllable of two alternative modes of presenting linen to flour paste-coated subject.

The mode? What I call LOTTO (Linen On Top, Then Overlay) - a  towel - gently pressed downwards. That's as distinct from yesterday, using the less manageable LUWU (Linen Underneath, With Underlay, which gave excessive lateral distortion).The imprinting medium? Yes, a simple paste or glue of plain white flour and water, mixed to give a runny consistency.  Stage 2 development of tan-colour? Simply pressing with a hot iron.

Photoedited image? Certainly.  used the same settings as the earlier ones for the Shroud Scope image(-7,100, 15). Fix? Judge for yourself. Here's the unedited photograph, prior to rotation to assist comparison with the Shroud.

"As is'  imprint., withoit photo-enhancement.
Note the relative absence of lateral distortion. Was that entirely due to using LOTTO instead of LUWU? No. There's a simple way of avoiding lateral distortion in this model. Apply paste only to those parts of the relief that one wished to be imaged, i.e. the highest relief, to get a bas relief type effect, avoiding the sides.

Is the image reasonably permanent? Impossible to tell, unless one has a handy cathedral in which to store it, and lots of patience (several centuries at least). But the image does withstand (a) repeated rinsing  and wringing out with cold water, drying and ironing:


Water-washed, before (left) and after (right) photo-enhancement (-7,100,15)


and (b)the above,  followed by application of soap and water, followed again by drying and ironing.


Soap -washed, before (left) and after (right) photoenhancement (-7,100,15)


Conclusion:there would appear to be nothing in the least bit mysterious about the 2D image characteristics of the Shroud image, once it is appreciated that the image is a contact imprint (the negative light/dark reversed nature of the image alone should be sufficient to conclude that the image is an imprint - NOT a painting, not even a faded, degraded painting).

What about the "profoundly mysterious"  3D properties of the Shroud image? Do my imprints respond to 3D enhancement in ImageJ?

Judge for yourself, dear reader:

3D rendering: click to enlarge
Finally: light/dark reversal (to change the negative imprint to a pseudo-positive image, mimicking a photograph, as per Secondo Pia (1898)?

Simple light/dark reversal in Image J
As above, with 3D enhancement.

That'll do for now. Publish and be damned.
I say the Turin shroud is a medieval fake, produced by a simple two stage procedure: imprinting with an organic substance (which may well have been white flour, which has convenient adhesive properties)followed  by second stage colour development (thermal in this posting, though chemical development is also feasible - see previous postings which used nitric acid or limewater).

Update,  Thursday 25 June: I shall repeat the above experiment today using my wife's crossed hands instead of my own. To show the versatility of the technique  there will be subtraction of an unwanted feature (rings), simply by taping over, thus protecting from the imprinting medium and, conversely,  maybe the addition of something else, e.g. paste in an area that would normally escape imprinting.



 The result was broadly similar to the one above, except for the additional tests. The location of the protected ring can be see as a blank rectangle.There  blank region  where one hand abuts on the other was marked with three small dabs of flour paste from a paint brush. What these tests show is the ease with which wanted or unwanted features can be added or removed by masking or 'doctoring' the imprint prior to colour development.

The 3D-rendered version of the above image was somewhat disappointing:


The reasons are probably technical, to do with using too viscous a paste which did not apply evenly (see banding on right wrist). You win some, you lose some.

I shall also make a start on that Appendix (why the TS is an imprint, not a painting), but build it up in instalments (no need for a rush job: what's another few hours or days extra on a 3.5 year project now drawing to a close?). Expect the first 3 or 4 points later in the day. (They were added, and have since disappeared - the Blogger Editing Bug is back!)

Simple answers to simple questions

1. But what about the blood? You have to explain the blood.


The priority on this site has been the  "enigmatic" body image (negative, superficial, 3D properties, impossible to reproduce by any known technology etc). So why divert attention to the blood when confronted with answers to the supposed image conundrum?  Blood can wait till later (while noting that the new procedure allows the forger to 'paint' the subject with imprinting medium first, then 'paint' with blood on top of imprinting medium, then imprint, thus ensuring there's a strong, direct contact between blood and linen with imprinting medium on top instead of underneath (in agreement with the Adler/Heller results with protease enzyme).

2. To stand any chance of being taken seriously, you will have to match every single detail of the Shroud.

No I don't. The Shroud we see today is unlikely to be the same in all respects as the one that existed 700 years ago or longer. What has to be matched in a scientific approach are those features that make the Shroud uniquely different from all other images from the pre-photographic era, notably the negative image, the absence of known pigments, dyes etc, the extreme superficiality etc.

3. There was no white flour in medieval times, and even if there had been, it would have differed from the modern flour used in your experiments  (genetics, added chemicals, nutrients etc.)

Flour in my experiments is a forger's 'proxy' for bodily sweat, because it makes a good imprinting medium, being sticky, and because it's easily convertible from white to yellow with heat or chemicals. However, the forger may have used something different that served the same purpose - imprinting medium/source of yellow colour. So it hardly matters whether white flour was available or not. In fact, it's a common misconception that white flour only became available after the arrival of 19th century roller milling. The well-off with deep pockets could purchase white flour, which was easily if laboriously made by sieving stone-ground wholemeal flour through fabric screens to remove the large particles of bran and wheatgerm embryo).

4. If the technology for forging the Shroud existed in the 14th century, then why is there only one Shroud?

Answer: because someone who had the resources to fabricate a convincing holy relic, one that can be claimed to be the actual linen used to envelop the crucified Jesus, would have needed to ensure that the technology remained a secret known only to the perpetrators. It would have compromised the mission objectives entirely if there had been so much as a single prototype version abandoned in the corner of a workshop.

5. What gives you the right to insult the intelligence of scores of academics and professionals, many with distinguished records of research, with your tacky simplistic model which you yourself have described as a Blue Peter 'make'?

If the model were that simplistic, this retired researcher, who also has a record of research and modest achievement, would not have needed 3.5 years to conceive of it. The trouble with arriving late to an active area of research is the deadweight of 'received wisdom' that in many instances has hardened into rock-solid dogma. It's hard not to be influenced by the big cheeses of Shroudology who descend onto websites to say one is barking up the wrong tree, that such and such was discounted decades ago, that one should "go acquaint oneself with the literature". In fact the current model incorporates many existing ideas - from Ray Rogers, Luigi Garlaschelli, Hugh Farey and Joe Accetta. But the key aspect was the realization that the body imprint was intended to represent ancient yellowed sweat, that it was not intended to represent a product of post-mortem putrefaction, nor a miraculous image imprinted by a flash of highly energetic radiation, of a type unknown to science, a signature of  resurrection, or as some would have us belive, a love-letter to modern man (that being the case, why the 'wrong' answer for radiocarbon dating?).

6. It's just a rehash of the scorch hypothesis, and we all know that was ruled out a long time ago (only the most superficial layers of Shroud fibres are affected, no change to the central medulla, lack of uv fluorescence etc).

Sure, the current variant uses heat to develop the Shroud-like coloration in the imprint, but the temperature needed to do that was insufficient to affect that of the non-imprinted linen, except maybe for an exceedingly faint tinge which could be mistaken for aged linen (a beneficial effect?). But other alternatives exist - like nitric acid and other chemicals. Scorching is just one way of producing yellowing, one that requires pyrolysis (thermal degradation) of the linen fibres themselves. Use of an extraneous coating layer (flour etc) opens up additional possibilities where chemistry is concerned (caramelization of sugars, Maillard reactions between sugars and protein, nitration of proteins etc).

Update 30 June: comment posted to a  Telegraph article (Science section) by Lily Willis:


The real reason your eyes go red after swimming isn't chlorine, but urine

ColinB


















ColinB an hour ago 
 

It's not news. In fact, it's been known for decades that chlorine reacts with the nitrogenous waste compounds of sweat, urine etc to make nitrogen trichloride (NCl3). The pure compound is an oily liquid that is highly explosive. Yes, it has a very strong and distinctive smell of stale over-subscribed "swimming pool" (unhygienic ones that is). As the article indicates, a "shock" treatment with surplus chlorine helps break down the NCl3, but is a last resort, prevention (pre-showering and/or bladder control) being better than cure.

On a different matter I'd like to tell science writer Lily and anyone else who's interested about my latest experiments for modelling the Shroud of Turin image. I think I know how it was done. Anyone interested? Do you read the comments under your own article Lily? I call it the Blue Peter method (needing only linen,flour paste and a hot iron) but it took 3 years of hard slog with scores of progress/lack of progress reports to figure it out!

The breakthrough came when I realized that the Shroud body image was intended by its medieval fabricators (forgers?) to represent a SWEAT imprint, so in a sense there's an affinity with this topic of bodily secretions and their aftermath.
ColinB

(Link to this site)

Update: Sunday 28 June  11:20 French time (unrelated to Shroud)

So what caused the terrible fireball at the Taiwan water park gathering, leaving hundreds with serious burns?




So far we've been told next to nothing about the chemistry, except that a "coloured powder ignited".

If one looks at the video clip that accompanies the BBC report (see link) one sees a cloud of white vapour coming from the stage immediately before the conflagration. At a normal gig that would be the fog produced when dry ice (solid CO2) is dropped into water.

Dry ice and water - NOT the effect used at the Taiwan water park.
But CO2 extinguishes fire. Might it have been liquified propane or butane instead, as used in spray cans etc? In other words, it wasn't the coloured solid, whatever that was, that was the culprit, but a flammable gaseous propellant. Propane gas (C3H8) has about 1.5 times the density of air, butane (C4H10) more than double, so would tend briefly to hug the ground before dispersal via diffusion. We shall see. Burns are terrible things. My sympathies to all the victims and their loved ones.

Update on that BBC report:  14:25 French time

"The fire department said the powder ,used to create a party atmosphere, may have ignited due to the heat of the lights on the stage, or from sparks from machinery.
The substance is also used in other countries. It is made of dried corn and can be highly flammable, says the BBC's Cindy Sui in Taipei.
The 519 victims were sent to 41 hospitals, and 413 are still in hospital, say municipal authorities."

Flammable solid maybe, but it still needed a propellant gas to shower it over the crowd. I still suspect itr was the propellant gas that ignited first.

Update 16:40

Here's a freeze-frame from the video clip that accompanied the Telegraph's report:

Video still: Taiwan water park, immediately prior to fireball

A instant later, the white cloud of vapour (butane?) was replaced by an orange fireball.

Update 18:30 Sunday 28 June

This science bod finds accused of "extreme blogging" and been book-ended with Stephen E. Jones of Perth, Australia

Reminder: this blogger has been reporting his attempts to model the Shroud in over 300 postings, here and on his specialist Shroud site, since December 2011. What you read here describes in moderate language the conviction that the goal is in sight - that the image is a contact imprint, obtained by a two step procedure.  Stephen Jones has done no modelling whatsoever. He is not a research investigator, certainly not in any experimental hands-on sense. He is perhaps better described as someone with a particular brand of hardline theology, one who is polemical - talking up those studies that are pro-authenticity, and attempting to dismiss, sometimes in the most contemptuous terms  those that aren't. The idea that the two of us are both extreme, opposite sides of the same coin, so to speak,  is a classic Porter windup, as was his concluding with: "Is there some way to put these two in a room together and tell them they can’t come out until they agree on everything?"  

This blogger sorely regrets the time and effort spent on communicating his evolving ideas on that site. Porter is a purveyor of glib. He has nothing useful to say - nothing whatsoever. He and his site merely act as a sponge for other people's content.

Update 29th June

Have decided to make a new posting of that frightful Taiwan fireball.

Returning to the Shroud, where are these mysterious locations on a man's recumbent body that could only have been imaged by "action at a distance"? Please list them.

Reminder: in the latest model, using white flour paste as imprinting medium, there is a truly amazing moulding of linen  to contours, as my photographs show. There is no need to invoke "action at a distance". That simply opens the door to pseudo-science (self-collimated radiation, unknown to science, wavelength unspecified, able to project an imprint across air gaps onto linen as if the latter were a photographic emulsion).

But then I've asked that before, several times, and received no response. Why bother trying to communicate with those who simply parrot their mantras and who refuse to respond in detail to one's questions and objections? 

I repeat: please specify the parts of the naked human anatomy that are visible on the Shroud image but which would be inaccessible in a contact-only model, with manual fingertip moulding.  A numbered list would be nice.

Further update:we're also told that there's an unacceptable degree of lateral distortion in my contact imprints of crossed hands. Really?



But the individual making that judgement of Solomon (same as the one above) cannot have read this posting in detail. One can have as much or as little lateral distortion as one wishes, depending on how much of the "sides" one decides to paint with imprinting medium, or indeed, tries to avoid altogether.  I in fact over-painted when doing my wife's hands, having strayed onto the base of the thumb, which explains that otherwise peculiar and unsightly bulge one sees in the imprint.

In fact, I  recently came across a paper recently (must try and locate)  in which someone was saying there was a small degree of lateral distortion in the Shroud image, and that it would be difficult if not impossible for a forger to reproduce it. Talk about wanting to have one's cake and eat it...

The usual response one sees to the crossed hands on the Shroud is that the fingers are too long, too bony, too x-ray like. Some have even gone so far as to suggest Marfan's syndrome!  Given the response to my own (or wife's crossed hands) as too distorted, we maybe have an explanation for those TS hands: the fabricators were so concerned at the prospect of "normal" hand imprints being seen as too pudgy or distorted they decided to err in the opposite direction, deploying a minimalist application of imprinting medium, and happy to hear the hands as somewhat skeletal, with fingers  too long and spindly. That's better than hearing them described as an obvious imprint. "Skeletal" at least implies death, preceded maybe with acute trauma.

Then there's the legion of folk queuing up to say "your image looks nothing like the one on the Shroud".

What they mean is, nothing like the original one that was on the Shroud, that may have well been subject to some 'toning down', if only as a result of the testing of its permanence in the years following its first appearance, compounded by the effects of centuries of wear and tear. (Link) Which brings us to the present: it's said that the image disappears if one tries to view it at close quarters. One has to step back 3 metres or more to see it's an image of a man. So how can anyone be so certain as to the 'look' of the Shroud image when their view is based on a limited number of photographs, more or less enhanced to improve contrast against background?

As I've said many times before, this researcher is not attempting to produce a facsimile copy of the TS, and would be unwise to do so, given the uncertainties of ageing etc. He's MODELLING the TS image, attempting to put ticks in all those boxes for the various key descriptors like faint, superficial, negative, 3D properties, no unequivocal reverse side image,  no uv fluorescence, no known pigments or dyes, strippability when fibres are pulled from Mylar adhesive tape etc etc.

There are those who seem to skip that list, and focus on characteristics like "image resolution" "fuzziness" etc, with little or no attempt to quantify. They may indeed be the ones that dictate first impressions when comparing the TS with model systems. if that is the case, then it's worth making clear immediately that these are early days regarding the present model. We know that washing the primary image in water, and then soap, leads to fainter, arguably fuzzier image. But there are other ways of achieving the same result, notably by using a progressively thinner, runnier flour paste (yet to be tested). What matters right now is the principle: the simple 'Blue Peter' yes-you-kiddies-can-do-this-in-your-own- home methodology ticks  a sizeable number of boxes, which is more than can be said for those high energy laser beams that so far leave nothing more than a tiny brown patch on linen (no image!). My medieval technology may seem primitive by comparison (deliberately so) but it does produce an image ( as a contact imprint)  as anyone can confirm for themselves, in their own home, in the space of 30 minutes or so.

Update July 6th

When the linen in my 'Blue Peter' model is thoroughly washed, first in water, then with soap, all that remains finally is a faint 'ghost' image. There can be so little there in material terms that it becomes a major headache in analytical terms determining the chemical nature of the chromophore. But that is equally true of the Shroud image layer too, where next to nothing is known re chemical makeup.Who can say whether it's a product of caramelization (requiring sugars and maybe oxygen only) or whether it's a Maillard reaction product (requiring sugars and proteins, or some other source of  amino groups?).  As I think I said recently, my model system could be handy for developing non-destructive spectral techniques for distinguishing between the two possibilities listed, and maybe more besides.

Is there anything that can be done in the meantime to get a rough idea as to what we're dealing with, specifically the type of sugar involved (given that both caramelization and Maillard reactions require free sugars)? Maybe. In Maillard reactions, it's known that pentose (5-carbon) sugars are more reactive than hexose (6 carbon sugars), while still needing elevated temperature (belatedly recognized by Ray Rogers, even if his fan club has yet to catch up). In other words, one should be focusing attention less on the major constituent of flax/linen  bast fibres (cellulose), or, if entertaining the possibility of coatings from flour etc, less on the major starch component. Attention should be on those parts of the linen and/or coating that provide pentose sugars. In the case of linen that is the primary cell wall that has a high percentage of hemicelluloses, and to a lesser extent the much more substantial secondary cell wall in which those pentose-rich hemicelluloses are also present, albeit at much lower concentration relative to the cellulose.

Expressed in these terms, there is a means of  testing whether pentose sugars play a crucial role or not in the Blue Peter image, and by hopeful analogy, the Shroud image too.  Cotton is mainly cellulose, with very little hemicellulose. So what I need to do is paste cotton and linen in the one experiment, then apply the same hot iron to both, and then check the intensity of the resulting mark or image before and after washing. Prediction: both will give a prominent pre-wash image, due to reactions involving the pentose sugars in the white flour. But there will be little or no ghost image finally on the cotton after washing, because cotton lacks the pentose sugars needed, whether in the primary cell wall (if present) or the secondary cell wall. I'll try to do that experiment shortly, but it won't be today, or even tomorrow. Shroud research is no longer my top priority, having resumed an interest in other topics that were shelved when Paolo di Lazzaro came along with his ultraviolet laser beams in December 2011, claiming  that the TS image could not be accounted for with conventional science. To which I say: OH YES IT CAN!!!

Update: Am toying with the idea of subjecting linen and cotton to a range of chemical pre-treatments, to see which if any modify the subsequent behaviour towards 2 stage imprinting. One would look at strong acid, alkali, bleach, SO2, boiling in water or salt or detergent, enzyme treatment (pectinase etc), organic solvents, etc etc. The aim is to get some idea of the nature of the physical or chemical interaction that allows the final ghost image, i.e. the one that remains after vigorous washing and rubbing with soap, to bond so firmly to the fabric.

Wednesday, May 6, 2015

The chemical principles behind the iconic Turin Shroud can now be explained. All that remains is to produce a look-alike copy.

Important update (13 May): for a 16 point summary of the new nitric acid model, see the new posting on my specialist Shroud site.
 
It's said that a picture is worth a thousand words. Here's a flour/egg yolk imprint done just two hours ago, photographed here after removal from the nitric acid bath, neutralized with bicarbonate, rinsed with water, shown here drying on the radiator, ready for processing in Image J (tone reversal as per Secondo Pia followed by 3D rendering).





Here's the above after further processing (click to enlarge).  Top left: the dried image after ironing flat. Bottom left: conversion to B/W, then a Secondo Pia style tone-reversal. Right: the secondary B/W image after 3D rendering (Image J).


It's taken over 3 years of almost non-stop experimentation, but this blogger/retired science bod is now able to explain how the faint negative image of the Turin Shroud was obtained (as a feat of medieval technology, aided by alchemists).

The task: produce a contact image that could be claimed to be that left by the crucified Jesus on Joseph of Arimathea's 'fine linen'.




It's incredibly simple in principle (why didn't I think of it sooner?):

1. Paint an adult human male (alive or dead) with an organic paste or slurry as imprinting medium (in other words, turn them into a giant rubber stamp). My preferred medium right now is a dispersion of white flour in cold water, but that could change).

2. Press linen against the subject (or subject against linen) to leave a moist imprint. Dry.

3. Develop the image chemically using a suitable reagent , one that converts the organic material to tan (yellow-brown) oxidation products (less probably Maillard reaction products).

My preferred reagent right now is nitric acid vapour, the means of production were known to medieval alchemists (notable "Pseudo-Geber" who may have been one and the same as an obscure Franciscan monk known as 'Paul of Taranto'

4. The yellow-brown aka sepia  imprint will be a 'negative' of the subject, inasmuch as the light/dark tones one sees in photograph are reversed. In other words, the highest relief  (nose, chin, forehead etc) will be dark, not light, and the lowest relief (eye hollows etc) will be light, not dark. They are light in a photograph as a result of reflecting most light. In an imprint, they are darkest through making best contact with a surface.

So I maintain that the plausible science is established - at least in principle-  so far as producing a negative  sepia 2D image from imprinting off a 3D subject is concerned.  Whether it matches all the additional or peculiar characteristics of the TS image (extreme superficiality, lack of reverse side image, lack of uv fluorescence, microscopic characteristics etc.) remains to be seen. However, let's insert a note of caution: not all those listed characteristics were necessarily there immediately after image formation, regardless of age - centuries or millennia. Some of those characteristics may be a result of ageing. At present it seems sensible to adopt a broad-brush approach, attempting to accommodate  only those 'headline' characteristics of the TS that have led to its being described as iconic or enigmatic. Where the latter are concerned, the prize for the most 'iconic' must surely go to the pioneering 1898 photography by Secondo Pia, which converted the Shroud negative back into a positive (by innocently treating the TS as a positive and convereting to a negative!).



It is the conversion one sees above that led to what must surely be the sound conclusion that that the TS negative image must be an imprint, probably a contact-imprint, one that on tone reversal allows one to see the 'real life' (or death!) appearance of the imprinted subject. It's for this reason alone that the dismissal by Charles Freeman of the TS as 'just another medieval painting' that has simply (and conveniently) lost its pigment over the centuries is so hopelessly blind to the implications of the negative image and Secondo Pia's spectacular discovery.

It's not sufficient, needless to say, to establish a scientific framework. There has to be a sizeable input of technology too. While history provided one or two pointers to the likely science (alchemy etc) there is no such  assistance where attempts are made to deduce the technology employed, i.e. applying the science in the manner that achieves the best end result. One does not even know for certain what the desired end-result was, or for what purpose, though I've believed it to be an attempt to simulate an ancient sweat imprint, ever since spotting that Veil of Veronica-like motif labelled SUAIRE on the Machy Mould for a Mark 2 (or Mark 1) Lirey Pilgrim's badge.  (It was that discovery more than anything that decided this researcher to abandon the idea that the TS was a thermal scorch, designed perhaps to symbolize the slow-roasting of the Templar leaders in 1314 for alleged heresy and other indiscretions. That seemed plausible given that one Geoffroi de Charney died alongside Jacques de Molay (Grand Master), de Charney being thought by genealogist Noel Currer-Briggs to have been uncle to his near-namesake, Geoffroi de Charny, Lord of Lirey, first recorded owner of the Shroud in western Europe).

So the working hypothesis IS that the TS is a simulated sweat imprint, that an imprinting procedure using an organic material was devised, probably with input from an alchemist, to develop the imprint chemically so as to produce a more intense, more easily visible yellow or yellow-brown colour. What we see now may of course be a pale shadow of the original, given centuries of fading, image fibre attrition etc.  But there's an upside to that: one does not need to be too concerned about one's pilot techniques producing images more prominent and/or well-defined than those on the Shroud.

After preliminary and somewhat unsatisfactory attempts to image from first  my hand (reasonable result) and then my own face (the less said the better - see preceding posting) I decided to use up-and-over imaging of the toes on one foot. The scale is handy for the size of my jars with the wide necks and ground-glass stoppers for nitric acid vapour. One can compare LUWU and LOTTO imprinting in the same experiment (which may or may not be relevant to the imprinting of the real Shroud). LUWU = Linen Underneath With Underlay; LOTTO = Linen On TOP, With Overlay).

I'll conclude this verbiage with photographs of results with this new tootsie test system as they come. Here's are some photographed just an hour or so ago. More will follow later. There are no plans to write any new postings until the current round of technology-testing is complete. Whole face imaging has been shelved for now. (Maybe Luigi Garlaschelli was right - a bas relief was needed for the face).

Imprint of toes onto linen (left) versus cotton (right). Imprinting medium: white flour/cold water only.



As above, after use of autocorrect in MS Office Picture Manager.

The lower half is a classical "footprint" obtained using LUWU configuration. The upper half is an imprint of the tops of toes obtained by turning the linen up and over, and gently pressing (LOTTO configuration).

More pictures to come (testing of egg tempera as imprinting medium etc).

Yes, egg tempera was the vehicle used as vehicle for paint pigments in medieval  times before the appearance of oil paint in the Renaissance. Despite being primarily egg yolk egg tempera not only attaches well to surfaces but is surprisingly durable. If searching blind for technology that might have been used to add flesh, so to speak, to the fundamental science, it would be unwise to ignore so common a commodity as tempera. In fact, there's one compelling reason for thinking why it may have been used, if only as part of a mix of ingredients: if the aim was to simulate a sweat imprint, it helps to have a visible yellow imprint before the chemical development (or indeed as a Mark 1 undeveloped imprint) given its yellow colour.

Here's the result of imprinting onto linen with a mix of flour, egg yolk and a little milk as extender.




...



Here's a comparison of three imprinting media:left- flour ; centre: egg yolk; right: flour + egg yolk. All had a little extra milk as extender (having been added to egg yolk to bump up the volume I decided the others should have it too).


Note the poor imprint on this occasion from flour "only". Well, as stated, is wasn't flour only. It was flour with a little milk. An immediate difference was noted compared with flour without milk - there was much less adhesion to the skin, much less force needed to pull the linen away from the skin.

The adhesion effect has been commented on earlier, with the observation that adhesion helps produce an instant high-fidelity imprint. That's due to the amazing ability of flour paste or slurry to stick onto so many different surfaces (this blogger has a photo album he made as a small child in which flour was used as an austerity-era paste - most  of the photos are still where they were stuck). A reasonable working hypothesis might be that milk has weakened the adhesive power of the flour. Good or bad thing? At first sight bad, because it means less flour attaches to the linen (probably) giving a weaker imprint. But might there be an upside? Possibly, as will be discussed shortly.

Yes, one encounters something quite unexpected when imprinting with flour paste. The linen quickly absorbs the liquid when pressed against the skin, such that the latter seems almost dry when the linen is peeled off. That makes for a good imprint, obviously, with so much flour transferred from skin to linen. But there's a possible downside. If transfer is complete, or nearly so at all contact sites, regardless of applied pressure, angle of contact etc, then how can the image be expected to show the 3D properties of the TS image. For 3D properties there needs to be some systematic factor at work such that variations in relief (height above a reference plane obviously, but maybe more subtle factors too) are captured in an analogue process to give variations in image intensity and subsequent 'apparent 3D' properties. That cannot happen if the medium transfer is too efficient at all points. So it may be necessary to include an additive, one that our medieval artisan might have included if only to make the adhesion weaker (he would not have been worrying about final 3D properties!).

Reverse-side imaging?  Yes, there's some at present, as the next pictures will show. But a medieval forger would probably not have wanted it either, if it gave the slightest clues to how an image was faked. This is where technology as distinct from science needs to be harnessed: finding simple ways of reducing or eliminating reverse-side imaging in the proposed flour/water model.

Here are some thoughts for a model system that focuses specifically on  efficacy of medium transfer as a function of 3D relief:

I would use the knuckles of my clenched fist as the 3D subject I'd paint the knuckles with various imprinting media (flour +/- milk +/- egg yolk etc) that had been coloured up with some ink or pigment, then press into fabric (probably re-using linen from previous experiments). The aim would be to find  a mix where the knuckles were imprinted more prominently than the rest of the fist, through having the highest relief. It would probably need to be a stiffish mix, whatever the ingredients, so as to avoid the mix being squeezed off the extremity down into the furrows between knuckles - not what one wants when trying to capture 3D relief!

Update Thursday 19:14


The footprint (mine!) top left was imprinted onto linen using a mix of white flour, egg tempera and a little milk. The image has been tone-reversed in ImageJ (bottom left).  The latter has then be 3D rendered (right).

The initial imaging was performed by standing on one foot, with a view to getting the best impression, but that was maybe not a good idea in retrospect: pressure would have forced the imprinting medium off the highest relief, eg the flat of the toes, resulting in less-than-satisfactory 3D-imaging.

Friday May 8

Here's the result of my fist-imprinting experiment. The result was disappointing, as will be seen, probably through an inappropriate choice of imprinting configuration (LUWU instead of LOTTO) that will not be repeated.  Iwill show it, however, and for 2 reasons. First, this is a real-time account of a research project, warts 'n' all. Second, as is so often the case in reseacrh, while an experiment may fail in its primary purpose, it can lead to unexpected and interesting side-observations. There was not just one, but two of those in the "Fist 1" so I'll now provide an, er, blow-by-blow account.

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Here's the consistency of the highest of 5 concentrations of flour/water dispersion tested.




Paint fist.

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Press fist into strip of linen, starting at the far left.


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Here's the imprint on the linen.


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Now add a measured volume of water to the flour/water mix with stirring to make it less viscous.



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Now repaint the fist with the runnier mix.

Repeat the process of diluting and re-imprinting 3 more times, working left to right along the strip.





Here's the final strip, with its 5 scarcely visible flour imprints. They will first be left to dry on radiator, and the linen then sewn to make a flat hoop, imprint on outside, to be suspended in nitric acid vapour over conc. nitric acid solution.





Here's the strip inside the 'developing tank', with a glass plate over the top. The clothes pegs were intended to keep the linen clear of the liquid acid.


In fact, one single linen thread had dangled down into the acid, drawing the latter up by capillary action.  A quick rep-adjustment put a stop to that, but the instant image development in the wet area gave an idea for another experiment, results of which will follow this one. The idea: to compare nitric acid vapour versus liquid solution as a developing agent.



Here was the linen after image development in nitric acid vapour, with the 5 fist imprints going from left to right.






Here's the same, with added yellow lines to act as dividers.


And here's the reverse side of the linen, with very little 'reverse-side image' - confirming that flour/water is a good imprinting medium in principle, despite there being much R&D still needed to produce a TS-like image.

Discussion

While the method works reasonably well for flat(tish)parts of the anatomy (see earlier results with the back of my hand, sole of foot) it does not like complex relief (face, clenched fist).

So those imprints above of my clenched fist are maybe difficult to recognize as such. But as hinted at earlier, it was a mistake  to have adopted the LUWU mode of imprinting. I had thought that passive pressure would give the simplest most recognizable imprint, but that was not to be, probably due to the right-angle turn at the knuckles , but other factors too, like excessive give in the underlay, and a possible rocking action. Never mind: the experiment yielded useful data in other respects as regards the possibility of using solution as a fast-acting alternative to vapour, and the virtual absence of reverse-side imaging.

The experiment also got me thinking about engineering the 'ideal' imprinting medium likely to yield the best 3D result.

The ideal mix will probably still flour as a major ingredient (large intact endosperm cells help reduce penetration and reverse-side imaging).  It will perhaps have egg tempera too, if only for its yellow colour, making it easy to know where to paint blood stains on top of body image. But it has (probably) to be paint-like in consistency and covering power, attaching first to skin, whether unwashed, with skin oils present, or washed (leaving unobstructed keratin, i.e. protein), but then transferring cleanly onto linen. There is now work to be done in identifying that mix, while at the same time maintaining credibility re the options that would have been considered in a medieval workshop.

Comparing nitric acid vapour and liquid solution as image developing agents






I reverted to LOTTO mode for this test. First paint back of hand with flour slurry (no additives).



Here again is that amazing 'cling film look one gets when placing linen on top, then pressing gently.


Here's the negative imprint - scarcely visible.


Now turn the imprint into a simple jigsaw puzzle. 2 pieces will developed in HNO3 vapour, two in conc HNO3 solution (70%).


Here I am adding the acid to one of those two pieces. Image development is seen almost immediately.




Here we are a few minutes later, with image development without noticeable leaching of colour, or migration from image to non-image areas. Success!



Here's the downside of using solution. There's a lot more acid that has to be neutralized before the linen can be removed for drying, ironing and photography.



here are the 4 developed pieces re-assembled. The image of the back of my hand is complete. There seems to be no reasons for thinking that vapour is superior to solution or vice-versa, at least where image-development is concerned.


And as before, there is scarcely any reverse-side coloration.

Next question: does one need concentrated nitric acid for development, if used as liquid? Might a lower concentration work too, albeit more slowly, but without the same degree of hazard?

Some quickie tests are in order, making serial dilutions of the conc acid, e.g. 70%, 35%, 17.5%, 8.75%  for a quick idea.

Come to think of it, use of nitric acid solution raises new technological possibilities. Let's suppose that the essential ingredient of the imprinting medium - provisionally white flour - is fixed instantly to the linen. But suppose there were additives in the medium that gave it a more functional paint-like consistency that were undesirable as left-overs in the final image. What is they were not fixed by the acid?  Maybe they could leach out into the liquid acid (not possible if vapour used), so that one was left with the just the chemical constituents needed for the 'right' kind of image.

Results: testing nitric acid solution as  developer, with a range of concentrations:



First, a paintbrush loaded with white flour dispersion was used to make a trellis pattern on linen. After drying squares were cut out for immersion in different concentrations of nitric acid solution.




Here are the squares in pots with the indicated concentrations of nitric acid (w/v). This was after about 30 minutes of contact. Pronounced orange colour has developed not only at the top concentration (70%), but at half that (35%) and half that again (17.5%). Only at the lowest concentration tested (8.75%) was there no unequivocal colour development.



Here are the same samples after 1 hour in acid, neutralization with sodium bicarbonate and partial drying on a towel.

Conclusion: the model works with nitric acid solution as well as vapour. What's more it's not necessary to use concentrated nitric acid (gives off fumes, hazardous).  It works well (and fast) with nitric acid diluted with water to 4 times its initial volume, i.e. to 8.75%, which  at approx. 2.75M is only a little higher than the concentration of bench dilute nitric acid (generally 2M).

Imaging of forefinger using the new quickie liquid developer (nitric acid SOLUTION) to compare different imprinting media.

Here's the final 3d-rendered image (posted first to allow transfer to shroudstory as progress updateI.






The stages in obtaining that image will be added later.

May 8, 19:12

The above 3D image was obtained while the test linen was still wet and drying on the radiator. (Man in a hurry).

The sample has now fdired and been pressed with a steam iron. Here are the definitive pictures:



The as-is imprints, after development in nitric acid solution.


As above, after tone reversal in ImageJ.  (A Secondo Pia transformation of a negative imprint back to a positive - or at least a pseudo-positive).



 
As above, after 3D rendering in ImageJ.

Now, back to the start:


Ready to start imprinting: flour slurry in the pie pot, egg yolk in the glass, and a 50/50 mix of the two in the egg cup.



After imprinting, drying on a radiator before chemical development. Note however the almost photograph like character of the egg yolk imprints, especially on the left. There's absolutely no reason why medieval folk should not have seen that kind of realistic imprint, albeit as a negative image. All that was need to produce trhe TS was to think up a way of fixing that egg yolk (or similar) image to make it permanent, maybe with some colour reinforcement.



And here's the new simplified image development step - simply immersing in nitric acid solution, 10% w/v and upwards. The lower end of the range is recommended to reduce fumes.

Update Saturday May 9

Feedback from Dan Porter's shroud story site (from Thibault Heimburger MD) and my response:

Thibault HEIMBURGER
May 8, 2015 at 4:52 pm
I have to admit that Colin’s work is very interesting.
In fact, it is the best work (still in progress) I ever seen, based on the “chemical imprint” hypothesis.
The fact is that the TS image is an “imprint”, not a paint, is obvious.
The fact that the TS image is a contact-only imprint rather than a contact+non-contact imprint is still undecidable.
Hopefully, at the end, we will see if the best contact-only hypothesis (the “chemical imprint”) can match or not at least the macro properties of the TS image.
Colin wrote (see his blog): “The task: produce a contact image that could be claimed to be that left by the crucified Jesus on Joseph of Arimathea’s ‘fine linen’.
Not only that.
The TS IS such an image. But this image has some fundamental properties.
So, we will see.
Sincerely, good luck.
May 9, 2015 at 12:07 am
Thanks Thibault. Your comment is most gratifying, and shows true generosity of spirit, given our differences in the past.
In an earlier comment here yesterday, I was deliberating on what should be the ideal consistency of the imprinting medium in order to achieve best 3D effects. I said it should be paint-like, i.e. tacky and viscous, so as to stay where applied on the 3D subject, since if runny, it would flow off the highest points of the relief down into the hollows and mess up the 3D rendering.
Oops. I was forgetting that gravity can be made to work for one. If you want a liquid imprinting medium to stay put on the highest relief, and indeed concentrate at the highest points, then turn the subject (or template) upside down before imprinting, and press it DOWN into linen.
There are two types of subject-to-linen presentation one can use when imprinting, what I have previously called LUWU (Linen Underneath, With Underlay) and LOTTO (Linen On Top, Then Overlay).
Use the LUWU configuration(even if easier said that done where real people are concerned). That requires painting the subject with imprinting material, then lying face DOWN into the linen to imprint the FRONTAL surface. If the medium is fairly runny and mobile, then in the brief time the subject positions himself face DOWN, the medium runs to the LOWEST points of the relief, due to gravity, which would have been the HIGHEST points when face up. It is the concentration of medium at the new lowest relief that might generate most if not all of the negative and 3D properties of the final 2D imprint.
OK, so it might be tricky to get a clean imprint via LUWU. However, the purpose in hinting at a gravity-aided model is not to suggest this was how imprinting was actually achieved, but simply to flag up the wealth of options on offer. Yes, one risks attracting unflattering references to Occam’s Razor. But having a range of options for modelling is not the same as needing to attach a host of qualifying assumptions to a model through having a limited range of options.


Further update Saturday May 9

Have just this minute taken a picture of the latest experiment in progress (imprinting off a plastic 'Galaxy Warrior" from Poundland), and inserted it as opening graphic (with a cut-and-paste to shroudstory which has just done an agreeable and benign cover on this posting).


Here's the same image after drying and pressing briefly with an electric iron:



Yes, as I said in the caption, the two heads - frontal v dorsal - should have been separated (a little) and the two images, frontal and dorsal, should have been perfectly aligned on the long axis.  As the sign used to say above the maintenance workshop at a student hall of residence I once stayed at: "The impossible we do immediately. Miracles take a little longer."

Update: 12May 2015

Here's a new result, hot from the press, correction, garage.



It's posted here first as a 'linkable' graphic. It will then be posted to Dan Porter's shroudstory site, so as to keep folk there in the picture. Where next? Maybe write a post on my  specialist shroud site that's been dormant since December last year, saying why I think this result is important. The colour you see in that pot with the handle, bottom left, may well be the one that is on the TS, albeit faded with time.

What's in the pot to give it that red-brown colour? It's the isolated gluten (the viscoelastic protein that is responsible for breadmaking dough) from wheat flour, washed free of its starch granules, then treated with nitric acid.  It's maybe a bit soon to be speculating on what is in wheat gluten protein to give so strong an orange colour with nitric acid (the so-called xanthoproteic test). My guess, for what it's worth, is the high tyrosine content of wheat gluten.  It readily nitrates with nitric acid to give the 'sepia' colour, as per TS.

The small glass dish on the right has the starch that was washed out of the wheat flour dough. It does NOT give the same red-brown colour, merely a faint yellow coloration, possibly, probably due to starch granule protein (friabilin etc, as discovered by my colleague Philip Greenwell at the previous FMBRA i.e. Flour Milling and Baking Research Association,   developer of the Chorleywood breadmaking process, now part of the Chipping Campden and Chorleywood Food Research Association

Posted to shroudstory:


 
May 12, 2015 at 12:13 pm
It says “figured out, sort of maybe” in the title. Might I humbly suggest there’s a bit less “maybe” now.

That’s isolated wheat flour gluten in the bowl at the back. That’s a portion of it treated with nitric acid to get the sepia (red-brown) TS-like colour in the dish bottom left. That’s the flushed-out, then gravity-sedimented starch fraction in the glass dish on the right, also treated with nitric acid, with faint yellow coloration only.
Why should wheat gluten (the protein fraction) of flour produce a orange colour with nitric acid? Answer: it’s almost certainly due to its high content of the phenolic amino acid tyrosine that readily nitrates with nitric acid in the so-called xanthoproteic reaction (used as a test for proteins).
In other words, the TS sepia colour is NOT due to dehydrated, oxidized carbohydrates, as suggested in the STURP summary. It’s due to nitrated protein formed by secondary chemical development with nitric acid of a contact imprint made from a human subject (dead or alive) using a slurry of white flour as imprinting medium.