New FAQs
Good ol' Dan Porter, take 1
take 2


Frequently Asked Questions
From the beginning of Wilson’s discussion of the Shadow Theory, there have been two universally asked questions. Here they are both responded to in brief. Additional questions have already been added and others will follow as they too become frequently asked.

1. Why would a Christian want to do this? Doesn’t attacking the Shroud hurt the Church?
Wilson’s answer:
This is not only a permissible thing for a Christian to do, it is something that, in principle, every Christian should want to do. Christians should hate lies, but above all else, lies told within the Church at large. Religious fraud isn’t only a lie about a thing (a miraculous healing, contact with angels, a relic, etc.). Religious fraud is a lie about the Church and Christ Himself. It is just another way of taking the Lord’s name in vain. We should want to debunk religious hypocrisy far more than we want to debunk secular hypocrisy. We should want lies gone because we love the Church and want her pure. I was very happy to publish my article on all this with a Christian magazine. Christians should be the first ones to holler if there is a possibility of deception within the camp. The world should never have to do our laundry for us.

2. The Glass Questions
a. How big was medieval glass? Could they make big pieces, or were they all little like those in stained-glass windows?

Wilson’s answer:
When I first presented the Shadow Theory, tentatively, to the student body of New St. Andrews College, I did not know the answer to this question. A member of my audience, however, did. As she had worked a great deal within an artisan glass shop that still used medieval technique she was able to describe the method for blowing a sheet and told me that sheets measuring 6'x8' were fairly common. When I looked into her explanation, before experimenting, I found that she was absolutely right. Throughout the thirteenth century glass blowers were capable of creating large sheets. They would blow cylinders, up to nine feet or more in length and then, while the glass was still molten enough, they would cut off the bowls that formed both the top and the bottom and slice the cylinder lengthwise, unfolding it into a sheet. The sheets would be cut into small pieces for use in leaded stained-glass windows, or painted while large.

As the Shroud is roughly fourteen feet in length, two pieces of glass would be necessary, both at least six feet long. The image of the front of the man would be produced beneath one and the back of the man beneath the other.

When Dr. Antonio Lombatti, Fellow Researcher in Medieval Church History at the Deputazione di Storia Patria in Parma, Italy was recently asked about the availability of glass large enough to produce the Shroud, he responded, “Of course a medieval artist could have enough glass to produce that relic.” He pointed out that six foot painted glass windows were not uncommon, and also mentioned that the length discrepancy between the front and back images of the man in the Shroud (1-2 inches) suggests two different phases of production.

b. So, medievals could blow glass sheets large enough for this process, but were they clear enough? Wouldn't the glass be flawed? How about other materials? Would an image made in sand directly on the cloth, or a thin painted fabric laid out on the linen have the same effect?
Wilson's answer:
Medieval glass, particularly Venetian, would have been plenty clear enough to allow for light penetration (it wouldn't need to be clear enough for us to watch the hummingbirds in the front garden). That is the first necessary step. As far as flaws go (wavy surface, air bubbles, etc.) at this point I can only extrapolate based on what I've seen thus far in my experiments. As I first began work painting images on glass, I soon realized that the sun's path was important for more than just the three-dimensionality of the image. My paintings, and those of the people helping me, were all positively cluttered with brush-strokes, and brush-strokes are not visible on the Turin Shroud. The theory went this way: as the sun travels it will expose every brush-stroke from a mathematically infinite number of points. The distinct shadow created by a brush-stroke would be dispersed along a line in reverse of the sun's path. In addition, the sun's route would shift a degree or two (or three, depending on the amount of time the linen was exposed), and the smoothing out of the brush stroke (and the linear path of that dispersal) would spread out in width as well. The cloth that was exposed beneath a sun lamp was used as a control for just this reason. When exposed beneath a stationary light source, the crudeness of the image remains, or worsens (with brush strokes visible). When the same image is placed over cloth beneath a traveling sun, the strokes disappear and the image becomes fluid. This same process would occur for flaws or waves in the glass. Some of the chunky spots on the painting I used are far more drastic than a glass flaw, and yet they are invisible in my image. Also, due to the proximity of the cloth to the glass (flush beneath it), potential refraction of light due to waving, would become negligible. Even more so because of a traveling sun.

As far as sand on the cloth is concerned, an image would certainly be created, but it would not be three-dimensional as there would be no gap between the sand and the cloth to allow for the sun's path to shift and sculpt the shading. A thin cloth would work, and is something that I have discussed with several people at times. It would only work if it were stretched tight over a frame (to create the necessary distance between the painting on its surface and the linen beneath it). The frame itself could not be too tall, probably no more than one half, to three-quarters of an inch. However, I find glass more natural and believable to a medieval forger. For one, glass accounts better for those never mentioned wrinkles on the cloth. There are regular constellations of wrinkles on the Shroud that predate the image-formation (there is blood in at least one of them). These wrinkles are generally the same color as the image on the Shroud, but occasionally appear darker. In the shadow theory, if a wrinkle were trapped beneath the glass, the linen within would be as protected, or more, as that beneath the painted portions. The result is a dark image, but also many dark wrinkles. I have yet to encounter any other explanation for these wrinkles, though there may be one.

In the end, like my initial testing of this image-making process, I can't know exactly how linen will react beneath medieval glass until I actually test it, something I hope to do this summer. However, I believe what I've learned from the disappearance of my brush-strokes, will apply equally well to glass flaws.

3. Have you performed any microscopic analysis on the linen in your Shroud?
Wilson’s answer:
"No," is the short answer. This experiment focused solely on the image-making process. Could I put a three-dimensional photo negative onto linen using a technique believable to a medieval forger? I can. So far so good. For the Shadow Theory to hold up in the long term, it will need to survive on the textile level. Tentatively, I would like to add a second wave to this experiment, imposing the same image onto a variety of linens. Fibers from each would then be analyzed and compared.

4. Didn’t Nicholas Allen already do this in the mid-nineties?
Wilson’s answer:
No. Allen’s experiment is quite spiffy, particularly his final images, but it is very different. What we have in common: We are both attempting to create a photo negative by means of sunlight. As far as I can tell, that’s about it. His theory (as I understand it) involves a medieval working with an early prototype of the camera. A corpse would be painted white and hung in front of the camera (obscura) for a number of days. The camera itself would be a large box with a quartz lense in the aperture and the film would be the linen, which had first been treated with light sensitive chemicals. The end results are phenomenally realistic three-dimensionally encoded photo negatives on linen. But Allen’s theory has never been widely embraced because his images so far outstrip the image on the Shroud itself, and because of the (apparent) implausibility of a medieval performing the experiment. Personally, I would like to believe medievals capable of what he describes, but if his technique actually had been the one used by forgers it seems that the Shroud would look a lot better than it does. As for my experiment, it is far less sexy. I paint glass and set it over linen. A photo negative is created, and it is three-dimensional. Another difference is the fact that Allen’s images are created by darkening linen with light (by means of photo-chemicals). Mine are created by the natural lightening of linen with sunlight, leaving only the dark behind. In both cases, a form of photo-technology comes into play (because light is used), but with my experiment, the forger does not need to be aware of the fact. Many people who hold to Allen’s position believe that Leonardo Da Vinci was responsible for the forgery, as he was most certainly a man capable of doing such a thing. But he was born in the middle of the fifteenth century.

5. If medievals were capable of producing an image this way, then why aren't there dozens of examples formed with similar techniques?
Wilson’s answer:
If a forger discovered this technique, I don't find it hard to believe that he wouldn't tell anybody about it. In fact, I would find it hard to believe that a forger would spread the good news of his newly discovered technique. In addition, to a medieval unable to see the image the way we can see it (in photos, or three-dimensionally rendered), the Shroud would not seem to be as wildly successful as it does to us. The forger and others would be left viewing it with the naked eye and would never see anything but the negative. The Shroud was obviously impressive to many but was dismissed by local bishops and even declared to be a fake by Pope Clement VII (ca. 1390) who required that a priest be present throughout all exhibitions of the cloth, declaring it to not be the genuine article. At the time, it could have been considered a successful forgery, but it was not really considered inexplicable until the first photos were taken in 1898. So it shouldn't surprise us that other similar forgeries didn't crop up. And as a medium, a photo negative on cloth would also hardly seem tempting for other uses. Would anyone really want an image of their wife done in a dark and light inverted medium? Of their son? A horse? This really seems to be the only use for such a technique, as long as the artist was unable to "develop" the negative.

6. What about Fanti's study, and the claims that the Shroud bears a second (and also superficial) image on the reverse side of the cloth?
Wilson’s answer:
Fanti's study is interesting, and it is also complicated, so it is possible (if not inevitable) that I misunderstand his work. To summarize it as best I can: a photo of the reverse side of the cloth was released by the Archdiocese of Turin (2002), and more recently Giulio Fanti and Roberto Maggiolo (of the University of Padua) created an "ad hoc" process for the extraction of an image and performed it on a digital version of the photo. What they found was a faint outline of the head and also some darkening that could potentially be interpreted as fingers and hands. I do not have the training or the mind to criticize the "ad hoc" process created for this, but I do have several questions about the assumptions latent to the experiment which I cannot answer by reading Fanti and Maggiolo's paper. Assuming that the "ad hoc" processes were on target and did reveal faint imaging on the back, rather than creating it (an assumption I am happy to make), I still have curiosities about the photos used.

I have been unable to find technical descriptions of the photos taken of the reverse side of the cloth anywhere, though I admit to not having searched too thoroughly. What I would like to know is the speed of the film, the type of lighting used, the color of the background behind the Shroud etc. Fanti and Maggiolo appear to be assuming that because the image on the front of the cloth has been established as superficial, and an image has been extracted from a photo of the reverse side of the cloth, that whatever appears in their photo must be superficial as well (since the center of the cloth has been shown to be blank). But as John Kerry's daughter can tell you of her embarrassing moment on the Cannes Film Festival red carpet, photography can penetrate cloth. Depending on the circumstances surrounding the photos taken in 2002, Fanti and Maggiolo may very well have identified the image on the front of the cloth in a picture of the back. Photographers I have spoken with have said that this would be more than possible. The assumption that what appears in a photograph only exists on a two-dimensional plane (the surface of the cloth) is a faulty one, depending on the lighting, film speed, etc.

At this stage, these are questions, not arguments. I don't know the photographic information, and when I do, these questions may be answered. But for now, integrating my theory with Fanti's findings does not seem as difficult as it first did (I had completed my experiment and submitted my article to Books and Culture, before this study was released). I do not need to discover how to place a superficial image on the reverse of a cloth already bearing a superficial image on the front. I need to produce a cloth with a superficial image on the front, and then be able to extract an image from a photo of the back (using photographic techniques similar to those used on the Shroud in �02 as well as using "ad hoc" digital image-enhancement techniques similar to those used by Fanti).

So, for now, I am undaunted by Fanti's findings, though I am aware that my confidence could yet vanish, as they say, like the morning dew.

7. Daniel Porter, online shroud guru, has blown you off, calling the shadow theory "preposterous" and giving Christianity Today [Books and Culture] a "Good grief" for publishing your article. Are his criticisms legitimate?
Wilson's response:
Porter's concerns (though they might be better described as out-of-hand dismissals) are very legitimate. If glass didn't exist in sheets large enough, then obviously this theory falls apart. The trouble is that glass did exist big enough. Porter cites the rarity of sheet glass in the seventeen and eighteen hundreds, but luckily that's not when a forger would need to find some. He posts a diagram of someone making spun glass, always created in messy circles nowhere near large enough. But cylinder glass blowing (creating sheets from 6x8 to 9x5) was a common technique beginning as early as the eleven hundreds, and used effectively through the thirteen hundreds. It would have been costly for a medieval to acquire, but not unfeasible.

As to all of Porter's chemical complaints: I was not trying to prove that the Shroud of Turin was faked using this method (though I believe it to have been). I don't yet have the data to make that sort of claim (if I ever will). I set out to prove something with a relatively narrow hypothesis, and I proved it. A medieval could quite simply create a three-dimensional photo negative on linen (even superficially) like the image on the Turin Shroud, without using paints, chemicals, or dyes. Whether the chemical attributes of a cloth exposed this way matches the chemical properties of the Shroud, remains to be seen. But a few comments nonetheless. Nothing Porter mentions disturbs me, and I've been aware of all of it for some time. I had the privilege of interacting with Dr. Raymond Rogers about this theory and the chemical data before his recent passing. He was kind enough to agree to help me with chemical and textile analysis of images placed on era linen beneath medieval blown glass (a follow-up experiment I would have been quick to begin were he still alive). His concern with my theory was that the fibers within and without the Turin Shroud's image showed a similar degree of sun damage, something I believe would be the case in mine once the image was bleached to superficial from the reverse side. As to how the surface of the image itself would react to sticky tape (as per Porter's concern) we won't know until we let it sit around for six hundred years. Porter admits that my image is somewhat/kinda/sorta three-dimensional and photo negative, but says that others have achieved the same effect by daubing paint on cloth. I don't feel the need to explain the problem with paint-daubing, or statue-rubbing, because I think Porter knows better.

In the past I've appreciated information he has made available, and I still do. His work has been very helpful. There remain all sorts of things that would need to be explained for this paradigm to be generally accepted as explaining the Turin Shroud (as is always the case with any new paradigm in any context), but it shouldn't be blown off yet.

8. Why should we listen to you? Do you really think you're qualified since you're not a scientist?
Wilson's answer:
Whether or not I'm not a scientist is not disputed. I tain't. But enough about me. Are my images photo negative? Does the sun's path encode them three-dimensionally? The fact is that they are, and it does. I'm not qualified as a scientist, but then a medieval forger would not have been either. One of my first assumptions was that if a medieval could do it, then whatever he used would also most likely be available to me, a Lit guy. And yes, I called in scientific back up. If Dr. Minnich had not provided me with some 101 guidance on how to set up an experiment, I would have flailed about. His help was much needed.

Of course, if I shift the emphasis of the experiment to a chemical and textile level, using medieval glass and replica linen, I don't plan on going to Wal-Mart to buy a microscope. I would accept the offers of some of the scientists from around the world who have requested samples of my linen, and ship stuff out to people who know which end of a microscope to look through. My role, after creating images (easy and uncomplicated, as it turns out) will be to collect and collate findings. I think Dr. Minnich has taken pleasure in the fact that I'm not a scientist, and hopefully not simply because some people consider it blasphemy, and an intrusion into a sacred grove. He has been asked by a couple people about my lack of AKC pedigree, and he has been kind.

"It is the irony of science that often someone out of the mainstream shoots an outside shot with such accuracy."

And also,

"Someone who isn't biased by all the previous experiments has a different perspective. That's often the way things work in science."

I will be sure to send him cookies.

9. Daniel Porter has turned up the volume on his criticisms of you and your Shadow Theory. He still says that there wasn't any glass six feet in length in the 1300s. He says that you were unaware of Fanti's claims that he had found a second (superficial) image on the reverse side of the cloth, that you have no understanding of the problem caused by the blood, that you say Rogers' findings "only just gained definite credibility" and that you blow them off as artistic arguments that prove nothing. Can you explain all this?
Wilson's response:
Because an AP story about the Shadow Theory went on the wire, quoting both myself and Porter, these questions have come in a lump. So I will try to answer them in a lump. But first, I can't resist some comments. This is all a great deal of fun for me. Being a Lit guy, it's not often that I get to be accused of shoddy science. It's quite novel. But then, being a Lit guy, I think I'm having more fun because this is all such a terrific story. Especially because the two current players�myself and Porter� who have been pitted against each other in the recent microcosm of the AP release, both appear to be non-scientists. I hope I am not insulting Mr. Porter, but I haven't been able to find much of a bio on him, though I did find a bet (winnings to benefit a charity) he placed a while back that no one would explain the Shroud before 2012. If he is a scientist, I'm sure I'll hear about it, and I'll stand corrected when I do. But for now, I can't help smiling.

I have no desire to get in a fight with Mr. Porter. As I've already mentioned, I've appreciated his site in the past and I'm sure I will in the future (assuming I ever want to even look at the word "Shroud" again). But that said, I'll respond to his criticisms as I can.

First, he accuses Christianity Today [Books and Culture] of shoddy work for printing my piece, and of ABC for running a story about it (and I assume Discovery News as well, since they did something very similar). As he has obviously read at least portions of my article, I assume he also read the conclusion. I am quite aware of the rules of logical proof, and I state very clearly that I have not logically proved the Shroud to be a fake. I tackled a very specific experiment: Could I, a scientifically untrained lit-guy, three-dimensionally encode a photo negative (like the one on the Shroud) onto linen, without the use of paints, dyes, or chemicals. Turns out that I can. This is something that no other theory of Shroud forgery has accomplished (I don't know if I should interpret Porter's removal of his comments that other theories did accomplish the same thing as a retraction, but I will). I can also make my image superficial. Now for the objections.

No glass. Well, I don't know what else I can say. All of my information, from every tangible source, has said that cylinder glass-blowing became common as early as the 1100s. But if it makes Porter rest easier, the same result should be produced by a painting on a thin fabric stretched on a frame.

You were unaware of Fanti's findings. Well, yes. I was unaware of them. Because he hadn't found them yet when I conducted my experiment and wrote my article. However, now that I am aware of them, I have responded. Porter is right. There is no way (that occurs to my mind) that the Shadow Theory could account for a superficial image on the front and back, and nothing in between. "Period." Ignoring the potential problems Fanti's findings also cause for authenticity, I will repeat what I have already mentioned above (responding directly to Fanti's claims). I don't need to produce a superficial image on the front and on the back, to match the Turin Shroud. I need a superficial image on the front, and a photo of the back, from which a faint outline of an image can be extracted using a digital "ad hoc process." Assuming that Fanti's "ad hoc" process was legitimate, which it very well may have been, I'm still not worried. It is perfectly possible that a photo of the back of the cloth could return data from the front. Photographs frequently accomplish such feats (much to the embarrassment of some). Fanti's assumption that the data in the photo he received and scanned into his computer, only existed on a two-dimensional plane (the surface of the cloth), is a faulty one.

The problem of the blood. In short, some claim that the image does not exist beneath the blood stains. Others deny that the blood stains even exist. Both claims can be found in the hallowed pages of Peer-Reviewed journals (peace be upon them), though I'm sure the peers were different. I don't feel at all qualified to comment on either. Both sides accuse the other of cheating, and as it is impossible to call the teacher and have everyone grabbed by an ear and taken in to see the principal, I'll just have to be content with not even having an opinion yet. I have been aware that if the very surface of the linen inside the blood stains is light, and not dark, that explaining it could be tricky. But I'm not sure just how we would know this (despite reading studies that think we do). The linen is, after all, stained with blood (or vermillion and ocher according to some). In addition, when it comes to bleaching my cloth from the reverse side (to make the image superficial), I have no idea how linen inside of blood stain reacts to sunlight. It just wasn't something I felt I should include in this round of experiments.

You're casting aspersions at Rogers. No, I'm not. Mr. Porter didn't follow my article. There have been people hooting and hollering "foul play" about the carbon date since it was announced. Those hoots and hollers have "only just gained definite credibility." Why did I say they had gained credibility? The correct answer is, "Because of Rogers' findings." Rogers is, in fact, the cause of the credibility. I don't know if he was right, but he might be. However, it doesn't impact my theory much at all. A handy place for some profiteering villain to grab a good burial shroud for purposes of forgery, is from a tomb in Palestine. Cue the middle-eastern bug parts, and Jerusalem pollen. Cue the alleged traces of burial aloes. Cue a very unhelpful date. It is possible for a carbon date to overthrow authenticity, but a BC date won't necessarily toss the Shadow Theory. As to dismissing Rogers' findings as "artistic argumentation," perhaps Mr. Porter read too quickly. That phrase had a different antecedent. It referred to arguments that the Shroud must be genuine because of artistic similarities between old icons and the image on the Shroud. And those arguments availeth nothing.

Thicker fibers in the image, caramel-like substance, etc. This isn't a surprise. Again, I have not yet explored the chemical aspects of my cloths (which will most likely happen this summer). But for now, this data does not necessarily explain away my theory (though who knows what will eventually happen). Linen fibers will shrink in sunlight as a result of dehydration. It is no surprise that the fiber inside the image would be thicker, with a looser surface. There remain a number of options. The cloth may have been already ancient at the time of the forgery, and all of its fibers may have born a nanometers thick carbohydrate layer (as a result of aging) before the bleaching. Forgers may have tried to apply some substance to the image in an attempt to "fix" or protect it after its creation. They may have tried to fix it (they certainly would have known it could be bleached out), they may not have (we don't actually know how dark the image was in 1350, or if it's been fading). I'm not certain that we'll ever know. I don't even know how bleached and unbleached linen age over the course of six and a half centuries. What I'll need to do is have some replica linen woven, place my superficial image on it (maybe treat the image with some melanoidin), and then let it sit for six hundred and fifty odd years, with a set timetable of when my descendants are allowed to fetch it from its box and expose it to light for a bit. Then we might know something, but for now, as Raymond Rogers told me in regard to this fibre discussion, "There is much to be learned from linen, and I think we are only just scratching the surface."

To throw this whole thing back into a nutshell: I have developed a theory. That theory involved a prediction that a painted piece of glass placed over linen would clear two of the greatest hurdles in the mystery of the Shroud, producing an image both three-dimensional and photo negative. A painted piece of glass did just that. This is the first Shroud theory (including authenticity) that actually clears those two hurdles (without photo chemicals and the invention of the camera). A cloth wrapped around a body, even a body that pulses energy (of any kind) in the moment of Resurrection would not make such an image. It would create (at best) a large scale Death Mask of Agamemnon�looking like a man had been flayed and his skin laid flat. Of course, this newly proposed Shadow Theory has not yet worked its way into all the corners, or encountered all the data. I don't know if it ever will. There remain so many variables on the chemical level that I don't know if moderns will ever get the sort of epistemic certainty about the Shroud that we always so desperately crave. And I don't think it matters. Faith is far more fundamental than what we commonly think of as proof.

I greatly appreciated the little interaction that I had with Raymond Rogers before his passing. He was encouraging and helpful, even calling my theory a "good approach" (though I'm certain he thought I was all wet). I would have loved to have had the opportunity to work with him on a follow-up to this first experiment. I told him that I had nothing to lose in this flap. If I am wrong, have I lost anything? My faith in the Resurrection remains. If I am right? What have I lost? So, Christ was wearing something else on the first Easter day. While I�in my humanity�am confident that the Shroud was faked, and even believe that I have figured out how, I have been wrong before. My NCAA bracket, for example, is a shame to myself and my family. But my bracket toasted in the first round, and this theory has survived well beyond that.

10. What about claims that sun bleaching merely accelerates bleaching that will occur naturally as the material is exposed to light. If your theory were correct, wouldn�t the image have already faded into the background as light exposure over time equalized the bleaching?
Wilson�s response:
There are two possible explanations (of course assuming my theory to be correct). The first is simple. The image may have already faded substantially from the original. We have no way of knowing how dark, or bright the image was in 1350. The fact that the shroud spends most of its existence in a casket would account for why any of it is still here, though the variety of times it has been exposed to sunlight would have faded it to some (unknown) extent. The other possibility (and slightly more probable in my estimation) is that something was applied to the image in an attempt to fix, or protect it from deterioration. That could have been done by the actual forgers, or even by keepers of the shroud hundreds of years later who were trying to preserve the relic. This could also potentially account for aspects of the �caramel-like� substance on the image-bearing portions of the cloth. Truthfully, the chemical aspects of a decaying cloth (or the chemical aspects of decaying, unbleached and bleached cloths) just wasn�t part of this experiment, so what I say here has to be taken as logical speculation. I do hope to produce images on a variety of linens (of different ages if I can get any), and then farm those out to the lab coats who know how to work microscopes. I think I will have much firmer ideas about chemical and textile issues, after that process is complete. This experiment focused on the ability of a medieval to produce a photo negative image that was three dimensional, which has now been established. Of course, chemical analysis of similarly produced images may be conducted elsewhere before I even get around to organizing my second phase. I mean, though my grandmother did tell me not to, I gave out my recipe.



Books and
"Father Brown Fakes the Shroud"


Read Listen

Emerging From Shadows:
A Canon Press Lecture


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