Does thermally-induced scorching of linen ALWAYS produce fluorescence under uv, rendering it invalid as a model for the Turin Shroud? Answer: most definitely NO.

Site banner: see how a simulated sweat imprint (my wet hand pressed down onto dark fabric) responds magnificently to 3D-rendering computer software (ImageJ) before and after tone-reversal (negative back to positive image). Remind you of anything? Like those supposedly “unique”  and “encoded” 3D-properties of the Shroud of Turin body image? For a more realistic aged/yellowed sweat imprint, see the many postings on this site since 2014 obtained with the aid of my Model 10 (imprinting off  parts, notably head and hands, of a real body (mine!) onto linen with white wheaten flour, followed by heat-development of the image to generate carbon-based and thus bleachable straw-coloured melanoidins via Maillard reactions between wheat proteins and reducing sugars). 

This is the second instalment of a 3-part series that looks at uv-fluorescence of model scorch imprints and/or burn marks in general. See the posting immediately preceding this one for a brief introduction, stating the long-overdue need to re-evaluate a previous claim, made by the President of the Shroud of Turin Education and Research Association in a comment directed at this Shroud-detective some 4 years ago (see comment, Feb 10, 8:20). Yes, this blogger/retired science bod was slated by Mr. Barrie M.Schwortz no less, Documenting Photographer for the seminal 1978 STURP team, just as soon as I had settled on thermal imprinting as a model system, inspired as it happens by a line or two in STURP’s 1981 Final Summary.

Here again are his exact words:

B S 1 feb 2012 scorch

Link to be added later


To buisness, using the simple uv lamp described in the previous posting, capable of showing the fluorescence in (a) security markings on bank notes (b) fluorescent marker pens  (c) the quinine in tonic water and (b) the riboflavin in Marmite (just).

First test: heated bas relief template (horse brass) pressed onto linen  4 times as it cooled to get progressively fainter imprints.


1. Horse brass direct thermal imprints onto linen, i.e. “scorch marks”, viewed under ordinary artificial light control, (no uv)

Apologies to any artistic aficionados for the horses being inverted. I wanted the faintest imprint closest to the uv lamp (as an afterthought).


2. Horse brass direct thermal imprints onto linen, i.e. “scorch marks”, viewed under uv lamp (at top).

Result: the bas relief scorches do NOT fluoresce under uv.

Note the use of the fluorescent marker pens to act as a reference. The highlighted numbers closer to the lamp show better fluorescence.

3. Here’s the same, using my old friend from previous Mark 1 modelling (these direct scorch imprints having now been superceded by the more recent Mark 2 “indirect” two-step flour imprinting technology). Yes, it’s the fully 3D brass crucifix, purchased in the weekly Antibes open-air market, still doing servic.e.



3. Direct thermal imprint from brass crucifix, LUWU configuration, i.e. Linen Underneath With Underlay. Control, artificial light.



4.  Direct thermal imprint from brass crucifix, LUWU configuration, i.e. Linen Underneath With Underlay. Under uv lamp (top).

Result: the imprint off the fully 3D template does NOT fluoresce under uv light.

What we see so far are imprints produced by jsu one of the three modes of heat transfer, namely conduction, requiring direct atom-to-atom contact with no air gap.  One should not ignore the other two modes – convection (rising hot air) and radiation, especially infrared. Is it possible to provide just those two alone, excluding conduction? Answer: yes, by using flat bed toaster  (found in a charity shop) with a low wattage electric element and metal grid (the latter conducting heat AWAY from the contact areas between linen and grid).

1. start heating with flat bed toaster

5. Here’s the setup. I’m timing the horizontal one-sided toasting of linen strips on the flat-bed toaster so as to get a series from lightly to darkly toasted (but no butter to follow).



2. scorched strips linen from fb toaster

6. Here are three of the progressively toasted strips side by side.


3. Under uv DSC01342

7. Here they are, plus a fourth, viewed under uv.

Again: the thermal imprints do NOT fluoresce under uv.

Here’s a variant on the above routine in which aluminium foil was used to excude most air and oxygen access, while incidentally eliminating the radiated energy from the electric elements, such that heating depended almost entirely on convected heat.

9. Linen strips toasted while enclosed in Al foil

8. Linen strips toasted while enclosed in Al foil


6. viewed under uv

9. Viewing the previously foil-enclosed toasted linen strips under uv.

Again, the thermal imprints do NOT fluoresce under uv, either the more scorched ends exposed to air, or the fainter scorch regions that had been partially protected by Al foil.

“All scorches fluoresce under uv”? Nope. With the single reservation that my uv lamp is not radiating across then entire range of uv frequencies (it’s UV-A of course, the longer wave, less hazardous form of uv for bank-note checking in shops etc) not shorter wavelength UV-B with its greater risk of skin cancer, eye damage etc) it is already clear that there is no truth in the claim that ALL scorches fluoresce under uv. So how did that false generalization arise? Answer: look at the earlier Shroud literature, and the origin is apparent. It was based on reports that the burn holes, or rather their charred margins, derived from the 1532 fire, fluoresced RED under uv whn tested by STURP.  Leaving aside for a moment whether a non -experimental “scorch”, produced by a fire some half a millennium ago under conditions that are a matter of conjecture(molten silver etc, more later), does that particular scenario – ie. full thickness burn hole – lead to fluorescence?

That is the final modelling that will be reported here, in order to keep the posting a reasonable length.

How does one model the 1532 fire? One can’t, but one can produce a full thickeness burn hole, first opening kitchen windows and putting the oven extractor on full speed, then switching on the ceramic hob. (Yes, this blogger’s home has perforce to serve as a makeshift laboratory).



10. This photograph needs no caption – speaking for itself


11. See the margins of the burn hole still glowing red hot. That’s the end-stage carbon burning away. This model is by far and away the most extreme of  any this investigator has tested previously  under the heading “thermal insult to linen”.



12.Good heavens! What do we have here? Red fluorescence under uv? Well, a suggestion of pink fluorescence at the margins. But is it real?

Yes, I used a bank note as the fluorescence reference here (see previous posting).  But something suggested that the pinkish fluorescence was not real, but some kind of artefact? Why? First, it’s seen mainly on the left, not the right. Second, more imporatnt, it did NOT appear pink to one’s own eyes. It only looked pink on the screen after uploading from the digital camera. There was another clue to it being an artefact (final picture in this posting):



13.  Yes. it’s a case of ” now you see it, now you don’t”  (pink fluorescence that is, only on camera, NOT visible with one’s own eyes).


I shall terminate this posting right now, approx 20:00 on Dec 16th, 2015, because adding more would simply detract from what is presently seen as the takeaway message, namely that scorch imprints used for modelling  purposes do not fluoresce under uv, and thus cannot be dismissed as invalid. Red, or maybe pink fluorescence under uv may or may not be a genuine feature of full thickness burn holes, whether produced by heat alone, or by Hugh Farey’s modelling on this site of molten metal (about which more later). Let’s stop there.

I shall also be adding a valedictory later in response to Dan Porter’s announcement  yesterday that he is retiring from blogging, leaving an abandoned  Marie Celeste site afloat on the blogosphere.

Last post(ing) for Dan Porter's site, captured 18th December 2015. End of an era.

Last post(ing) for Dan Porter’s site, captured 18th December 2015. End of an era.

Yes, we’ve had our differences, plenty, maybe too plenty, but he’s always been a smooth-tempered  old school gent, to be savoured and/or treasured like fine wine. This Shroud sceptic even gets some appreciative words in the ‘Last Post’. Best wishes for whatever your new direction brings Dan Porter. Maybe we’ll get to hobnob over a  beer one day. First, I have a task to complete – sussing out (as we Brits say) the Turin Shroud.

The third and final instalment in this ‘fluorescence’ optic will focus on my current preferred Mark 2 flour-imprinting model (see banner above).  It’s one that uses a thermally-induced Maillard reaction in the first of two steps. As to what is left on the linen after the second stage washing with soap and water is anyone’s guess. It might still be a Maillard product, but it’s not impossible that it’s simply superficially pyrolysed linen carbohydrates that have become thermochemically dehydrated by their proximity to a Maillard hotspot, while not being Maillard products themselves.

With the various distractions from shroudstory right now (some folk trying to get in a last swipe, with an ever more blurred demarcation line between representation and misrepresentation) I cannot guarantee to produce Part 3 this side of Christmas. Indeed, year’s end would now be a more realistic target, which coincides with Dan Porter’s stated deadline for folk to submit their last comments before he finally closes up shop for good.

First postscript: here’s a sneak preview of how the next experiment will be phased, using a single flour-coated hand imprint onto wet linen to check the effect of uv radiation on two variables simultaneously:

1. Degree of oven-toasting , by snipping individual fingers off the developing image at increasing time intervals in the oven.

2. Comparing each finger’s image before and after washing in soap and water (labelled A and B).

hand 2 after snipping DSC01436

Plan for fluorescence check on Mark 2 model (oven-toasted flour imprints of my own hand) to be reported in the next posting (Part 3 of this series).

Second postscript: here’s the draft title for a posting to follow Fluorescence Part 3, hopefully by year’s end.

A new hypothesis for explaining the first recorded appearance of the Turin Shroud in medieval France. Was it purposely designed to be worth a king’s ransom?

The idea has been forming in my head while reading a lot of the pre-Lirey literature that attempts to link the TS with the Mandylion/Image of Edessa etc. There were recurring references to holy relics being seized as battle trophies by invaders and taken home. Then there were numerous references to knights and kings being captured in battle, and then held to ransom, sometimes for extraordianary exchequer-busting sums of money. Geoffroi de Charny of Lirey, first known owner of the double-image “Turin” Shroud,  and the king alongside whom he died in 1356 at the Battle of Poitiers (John II “The Good” of France both had experience of being held to ransom.  (in the case of John one could say that it was France itself that was held to ransom by the victorious Black Prince from across the Channel). These ideas suddenly gelled last night, and an opportunity presented itself to post this swansong comment or two to the dying shroudstory site. See bolded passage.


December 18, 2015 at 6:22 am

Thanks for the vote of confidence, PHPL. But there are two problems. First, my blog does not have the upmarket software of this one, and I’ve no experience of hosting a forum site. More importantly, I’d be far too partisan, wanting constantly to mix it below the line, and probably being far too quick to show the red card to miscreants bar one (myself).

Folk are of course free to use my site as a kind of methadone maintenance therapy if or when suffering acute withdrawal symptoms, but as I say, it’s really a very modest affair, mainly personal research-oriented.

I tried my latest idea on a VIP this morning – the notion that the Shroud was commissioned to serve as a standby alternative to cash to pay part or all of a King’s ransom in the event of capture by the enemy. Alternatively, Geoffroi de Charny, himself having been captured and held to ransom in Brittany (see wiki) may have intended it for his own fully comp insurance policy. But I reckon it took a lot of expensive trial-and-error R&D to get the Shroud looking so authentic, and that probably needed asubstantial input of funds from King John himself, probably coinciding with the founding of the Order of the Star one year after his 1350 coronation.

The first hurdle of approval has been successfully surmounted – Mrs.Berry approves of my latest thinking.

The above comment had been preceded earlier on a different thread, same site, with this one (again, the reader may wish to skip to the bolded passage):


December 18, 2015 at 1:12 am

Before addressing your points in detail re the crown of thorns, or rather its more or less gorey end-stage manifestations, David G, let me first expand on what I was saying earlier re the strategic decision-making that preceded the simulation of a sweat/blood imprint on a look-alike proxy for Joseph of Arimathea’s linen (proxy rather than forgery, note, not knowing a thing about the motives its creators).

It was decided, mainly for practical reasons, to keep the basal background body image as simple and straightforward as possible, the only detail being in the face (bas relief?) and the crossed hands. Elsewhere everything else was blurred and ill-defined. But there was a theoretical rationale that could be deployed in the event of a medieval sceptic or know-all claiming the body image was too simple. It would be pointed out that it was created from sweat, and sweat is a mobile and runny substance, even oily sweat, so could not be expected to produce a sharp imprint that incorporated fine details of body anatomy or wound damage.

Having made that decision to keep the body image simple, there was a price to be paid in the imprinting of the blood. There had to be a compensating overkill – one that would dispel any foolish notion that the figure represented was merely a stylized artwork. Quite the contrary, there had to be a gut clenching paramedical immediacy and impact that in modern day reporting would have resulted in a sensibility-preserving pixellated photograph on the newspaper front page. No, for our secretive goal-oriented medieval imprinters, there was to be no prissy pussyfooting around in the manner in which blood was applied to the image. It had to be done in a manner that looked like the man had REALLY been flogged to within an inch of his life (even if the Bible gives no indication of that) crowned with deep penetrating thorns, nailed, crucified and finally lanced. There were to be no half meaures. Indeed, nothing short of 100% reality-imprinting would do, given the imperatives of what they had set out to achieve, the motives for which one can only guess at (though King John the Good’s Order of the Star offers fertile ground for speculation, especially if he had had a premonition that he would be captured and held to ransom at the Battle of Poitiers,1356. Maybe widowed Madame de Charny (Jeanne de Vergy) had not been fully apprised of her late husband’s and King’s game plan, using the ‘genuine’ Shroud as a down payment, and more concerned post-Poitiers disaster to provide for herself and her orphaned children?

This comment is already quite long and starting to deviate, so I’ll post this as a prologue and then return with the detailed haematology later this morning (my time zone). King John and his close buddy Geoffroi de Charny of Lirey will have to go onto the post-Apocalypse back burner for now, with maybe a speculative posting on my own site, sometime in the New Year.

Right or wrong, for better or for worse, you read  the king’s keep-for-a-bad day-at-the-battelefield ransom idea here or the last gasp shroudstory site first!

Third postscript Saturday 19th Dec 2015:

Want to see a logical train crash? The sort that says  a mouse is a perfect elephant, having a mouth, teeth, the same number of ears, eyes, legs AND a tail etc etc. ? See bolded passage:


  • Jim Carney
    December 18, 2015 at 8:15 pm

    Have a wonderful Christmas, birthday, and new year(s), DaveB. Of all the comments on this site, yours were the ones I most valued–and Louis’, too. Colin Berry’s often silly musings (my opinion), such as his recent “ransom” theory, were a good counterpoint to the ones I took seriously and a good test for a temperament that runs to the impatient. As for the Shroud’s authenticity, it seems overwhelmingly clear that it is genuine. That arguments are many and well-known but a basic starting point is the fact that it is a perfect photographic negative. Hardly something that could have been created by a medieval artist when photography, much less negatives, were unknown.


We have seen that logical fallacy appear time and time again, notably on the deplorable Stephen Jones site. How many times does it need to be said?  The ability to convert a negative image to a reasonably realistic positive one by means of photography does NOT make the original image a photograph.  Certainly, the original image is some kind of -graph, I grant you, almost certainly a ‘contacto-graph’ ie contact-imprint, but that’s as far as it goes. Logical fallacies are cheap today, cheaper than yesterday…

Fourth postscript, still Saturday 19 Dec

To those like Jim Carney above whose first reaction is to assume this private eye must be  barking up the wrong tree,  or simply barking mad, I suggest they try googling (geoffroi de charny ransom).

I’ve shown a few of the entries below , which I’m busy exploring right now. Note the closeness between the year (1351) in which  King John II is said to have paid a ransom to secure the release of Geoffroi (followed by the latter’s immediate ELEVATION of the latter in the royal court) and the first showing of the Lirey Shroud, approx 1355, i.e. a mere 4 years later. But 4 years is plenty of time in which to do a considerable amount of imprinting R&D, producing 3D enhancible NEGATIVE images, as this investigator can attest (first Shroud-related posting December 2011).


Some returns under a Google search. Input: geoffroi de charny, ransom

Some returns under a Google search. Input: geoffroi de charny, ransom

Do I hear distant mutterings that say this posting is turning into a shroudological striptease? Er,  guilty as charged…

How come I’m reading the above words for the first time, after researching the TS for 4 years, putting up some 300 or more postings on this and my other 2 sites,  putting 2000+ comments on shroudstory, and reading a vastly greater number of Dan’s postings and the comments they attract? How come?

How come that someone who spent most of his working life in biomedical research labs with nothing beyond GCE O-Level history (but two sons both with history degrees!)  is the one to unearth something so petently  noteworthy (and instantly Googleable) as a 4 year gap between Geoffroi de Charny having his ransom paid by the King of France, and pilgrims flocking to the tiny parish of Lirey to see the purportedly ‘genuine’ Shroud (oh, and buy the takeaway souvenir badge too). This is far, far too much of a coincidence to be lightly brushed aside as being of no relevance to the sudden appearance of the Shroud at that particular point in French history, with no back story worth speaking of, and indeed no attempt on the part of de Charny or his wife/widow  to provide a convincing back story.

Update: Monday 15th Feb: anyone wishing to see “fluorescence”, or rather falsely cited fluorescence, being peddled to serve a pseudoscientific pro-authenticity agenda, and an especially bigoted one at that, should take a look at this image that has just appeared on the Stephen Jones site (to which I refuse to link, don’t ask!) and its accompanying caption.

wrongly tagged by jones as Shroudfluoresce

No, it’s not a fluorescence photograph. Where did he get that idea? It’s simply a photoedited  Enrie image in which density has been colour coded – with highest density being red. No, none of the  red is due to “blood fluorescence”, given that the non-bloodied nose, beard, chin crease  etc are red as well as bloodstains like the “3 on forehead. The iron has  to be chemically stripped out of haem in order to see porphyrin fluorescence, as extensively described by STURP’s Heller and Adler. If it really were fluorescent image, then one could not accept Jones’s claim that it’s only the blood that fluoresces. The body image would have to b e described as fluorescent as well, albeit as yellow rather than red fluorescnce.

The image that one sees above is a ‘flat’ version of what one obtains in ImageJ’s “thermal LUT’ mode, which is a sub-program in the 3D menu, except that there’s no 3D-rendering. (ImageJ does not allow one to remove the slight 3D rendering that one sees with the z slide control in its minimal value of 0.1).

Update Tuesday 16th Feb

My suggestion that the above photo is not a uv-fluorescence photograph, but a photoedited Enrie negative has been challenged in the comments elsewhere. The photo we’re told is from the cover of the journal that published Pellicori and Miller’s work for STURP in 1981, while acknowledging that the entire picture is not INSIDE the paper (curiously we’re told it’s separated into two halves, upper and lower).

What can one say? If it’s not an Enrie negative, confusingly photoedited to make blood indistinguishable from body image – both being the same shade of red – then what is it? What information does it convey that is NOT in the Enrie negative?

enrie versus false colour


Which parts of the so-called fluorescence image are genuinely fluorescing? Aren’t we told that the only parts that fluoresce are the serum halos around bloodstains, of which there’s no obvious evidence above, and which would require close-up views of each bloodstain in order to discern anyway.

If one goes to this shroudstory posting from Dec 2014, then thanks to Hugh Farey one sees what a real uv-fluorescence photograph from the Miller/Pellicori paper looks like.


The chief observation is that the image is non-fluorescent – apart that is from occasional serum halos around the bloodstains. It’s the background linen that shows weak fluorescence, as pointed out by Hugh Farey, not the body image or the major pigmented areas that represent blood!

Should anyone still be in any doubt as to the true nature of that alleged “fluorescence photograph” which I say is simple a false-colour rendering of a standard negative, if not the 1931 Enrie, then an exact equivalent, look at the following comparison:

pellicori and miller image v enrie after thermal lut

Left: the contentious picture, allegedly one that is taken in uv light to show fluorescence of “blood”, at least according to Stephen Jones; Right: the Enrie negative after digital reprocessing in ImageJ’s Thermal LUT mode to convert image density to a colour-coded variant with minimal 3D rendering. Note the close similarity, especially in the way that image density due to blood responds the same as body image of comparable high density.



About Colin Berry

Retired science bod, previous research interests: phototherapy of neonatal jaundice, membrane influences on microsomal UDP-glucuronyltransferase, defective bilirubin and xenobiotic conjugation and hepatic excretion, dietary fibre and resistant starch.
This entry was posted in Shroud of Turin, Turin Shroud and tagged , , , , , , , , , , , . Bookmark the permalink.

7 Responses to Does thermally-induced scorching of linen ALWAYS produce fluorescence under uv, rendering it invalid as a model for the Turin Shroud? Answer: most definitely NO.

  1. Colin Berry says:

    Jan 1st 2016: New year’s progress report on the fluorescence issue.

    I have been deliberately holding back on producing the third and final instalment of the uv series. Why the delay? Well, it was to be focused on the preferred Mark 2 imaging system, the one that is boldly promoted in this blog site’s banner, i.e. the white flour imprinting model. I’ve been deliberating on how the methodology can be presented more as physical and chemical science, less as cookery, and think I have the answer.

    there are three and only three ways of delivering thermal energy to linen and any acquired image imprint: conduction, convection and radiation. The last of those has been ruled out of contention in any number of previous postings. Sorry John Jackson, Paolo di Lazzaro etc.

    Conduction? The Mark 1 technology, imprinting off a hot metal template, bas relief or fully 3D, relied on heat conduction. I persisted with it, despite (or because of) a lot of misleading or ill-informed criticism that need not concern us now, and only shelved it (temporarily to start with) when following up Joseph Accetta’s ideas on wet-imprinting with acidic dyes, mordants etc.

    That finally led to the current Mark 2 model, using dry flour on human skin, imprinted onto wet linen. It’s the details of the oven-heating stage that are now under the spotlight. Thus far, the wet imprinted linen has been laid flat on a metal baking tray before being placed in a fan oven (supplying blown/convected hot air). I suspect that the metal actually protects the linen (conducting away heat) while allowing the hot air to gently toast the flour imprint (via Maillard reaction etc). What’s needed, before testing for presence or absence of uv fluorescence, is a control system that dispenses with thee metal tray, which suspends the linen in the oven such that heat is supplied by hot air alone. That system might be described approximately as “thermal energy transfer via convection (natural or forced) alone”.

    That’s the practical side of the programme. There’s also, as mentioned earlier, a “blood” posting in preparation. Admittedly with the wisdom of hindsight, or so it may seem, it will detail how the blood testing should have been done to get a less equivocal answer. Miniaturized tlc separation of methyl-esterified porphyrins, visualized by their pink or red fluorescence under uv, and run against authentic porphyrin standards, will be the proposed technology. This retired biomedical scientist was seeing those attractive porphyrin bands on tlc (thin layer chromatography) back in 1972 when analysing phototherapy bile for bilirubin photo-derivatives. Bilirubin and other bile poigments are closely related to porphyrins needless to say, being linear (ring-opened) tetrapyrroles rather than cyclic closed loop variety. Both the porphyrins and the bile pigments retain the two propionic acid side chains that can be methyl-esterified to render the molecule less polar and more mobile on tlc.

    The technology is/was not difficult. What a pity that Rogers, Heller and Adler didn’t employ a chromatographic separation of any kind, being content to look for fluorescence in the entire extract, and thus scarcely qualifying as qualitative chemical analysis, far less quantitative or even semi-quantitative.

  2. Colin Berry says:

    Things are moving at a rapid pace (when not engaged in seasonal obligations) Hugh, especially after reading (a) the wiki entry on G. de Charny and (b) the splendidly detailed pdf from Dorothy Crispino (“Why did he change his mind?” – about wanting to be buried immediately outside the walls and foundations of his church instead of inside as originally planned). I think I know why (think below-ground level out-of-sight workshop/laboratory) and while the idea that the TS was someone else’s ransom payment to Geoffroi, I think it far mare likely that it was designed at least partly to be a cash cow, allowing reimbursements to those who time and again stumped up the necessary to free G. from his captors (he being serially prone to being captured in battle and held to ransom). Indeed I’m beginning to think that the 100 Years War, at least to begin with, was less about grabbing French territory, and more about grabbing Geoffroi de Charny and holding him to ransom. We English got so good at it, that when G. was appointed bearer of the Royal standard (“Oriflamme”) , we knew exactly where to find King John, capturing and holding the monarch himself – one of G’s deeep-pocketed benefactors – to ransom at Poitiers, and proceeded to top the hapless Geoffroi, he having outlived his usefulness to Ransoms-We-Like Ltd.

    I have a first draft prepared, and will deliberating some more today on the key details, especially if I get held up in traffic today while delivering prezzies. Expect a new posting in a day or two. Fluorescence Part 3 will have to go on the back burner. The bit’s between the teeth, such as are left after NHS vandalisation.

  3. Hugh Farey says:

    I’m a bit confused about the ransom thing. If the Shroud were made to ransom de Charney, then it would have ended up with his capturers, not with himself. If it were a ransom, then perhaps it was given to de Charney by someone he captured (an Englishman from the 100 years war?) in order to effect his release.

  4. Hugh Farey says:

    Now here’s a thing, which could explain all. The other day I took some cloth to our local blacksmith, who kindly heated an iron bar (about 8 x 5 x 0.5 cm) to 1000°C – which you can tell partially by the sudden loss of magnetism at the Curie point (770°C) and partially by the colour, and then dropped it on the cloth. The first sample caught fire and burnt to shreds quite quickly, even in a tin with the lid only allowing a tiny amount of air in, but the second, which was from a different sample, behaved beautifully shroud-like, and although we threw a bit of water in after 10 minutes, the chars were restricted to the area of the bar. All 32 layers were neatly scorched in decreasing sizes, just like the Shroud.

    So far so good, but now comes the interesting bit. Having dried out the cloth and laid it on the floor, I set up a camera to photograph a good sample burn area, and then brought my UV lamp up to check the fluorescence. In all my previous experiments, I have had the lamp on, and brought the samples to it to be photographed, but this I think must be the first time that I have observed the fluorescence from the moment the lamp was switched on, as it were. To my amazement, the first thing to see was a thin red fluorescent border around the char holes, and none around the various nearby scorch marks, just as described on the Shroud. You may remember that I have never observed the red fluorescence, in spite of determined attempts to scorch cloth in an oxygen-free environment. However, while I was getting excited about this, the lamp continued to heat up – it takes about 5 minutes to reach full power – and the red fluorescence disappeared, and the familiar greeny-yellow fringe took its place, around the chars, and around the scorches, just as I have observed before, as seen in your posting of 19 Dec 2012, “Guest posting from Hugh Farey (yipee – another science bod!): here’s a snapshot of his current studies of scorching and uv fluorescence.”

    So, it seems to me that neither your UV source, nor that of the STURP team, is/was powerful enough to detect the fluorescence around the scorches, although it may have produced a red fluorescence around chars. The implications are that, yes, scorches always fluoresce, but only at high power. There is thus no reason why the ‘image’ of the Shroud is not a scorch!

    I’ll be writing all this up, with photos, in the December BSTS Newsletter.


    • Colin Berry says:

      Fascinating Hugh. I’ll need to do a lot more reading before commenting in detail. First thought, however: have you considered interposing a sheet of plain glass to get a partial filtration of UV-A from UV-B?
      From wiki: Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm.

      One wonders if your uv source emits mainly longer wavelength UV-A initially, and then progressively more UV-B as it heats up (?). If that were the case, the glass might prevent, or at any rate attenuate the progression from red to green-yellow fluorescence. It may be something to do with pyrolysis producing more or less polycyclic aromatic hydrocarbons (PAH) with increasing scorch or char temperature, the PAH fluorescing red under UV-A, the less-pyrolysed products on the fringes needing higher energy UV-B to fluoresce yellow-green. But don’t let any of my “musings” (thanks Jim Carney) cramp your style…

      Yup. To that other matter: any thoughts on my latest de Charny/ King John “ransom” idea? Have you seen the latest postscript on the current posting? I was well and truly gobsmacked on getting those Google returns just two hours ago…

  5. Colin Berry says:

    175W! Wow. That is amazing, Hugh. The biggest tungsten filament light bulb I ever bought for the home was 120W as I recall, and that was far too bright except for the largest room in the house.

    My own uv bulb is a tiddler – a mere 4W. But it does show up fluorescence in all sorts of things, as stated. So any fluorescent chromophore in a scorch has to be an exceptionally weak one, surely, in which case that weakens any case made on the basis of those “1532” burn holes. Note the quotation marks btw. Are you intending to surprise us all in the New Year?

    Sorry about my settings having defaulted, holding up your comment. I’ll check them when I get home (am using someone else’s laptop right now).

  6. Hugh Farey says:

    Very interesting, Colin. My old experiments still fluoresce as cheerfully as ever. Could it be anything to do with the power of the lamp? Mine is an old “Black Magic” 175W bayonet fitting from either Thorn or Osram, if I remember correctly. They don’t seem to be made anymore: I can’t find them on the internet anyway.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.