"The body image is so faint that many find it extremely difficult to make out at all.  All photographs - not just negatives - effectively enhance the image, partly because they are reduced in size and therefore focus the image, and partly because film emulsion intensifies the contrast"...Turin Shroud, Revised Edition by Picknett and Prince (2006)

The Turin Shroud image of Jesus could be a primitive photograph.
Lynn Picknett and Clive Prince wrote a book called Turin Shroud – in Whose Image showing that there was nothing miraculous about the image and the face on it was the face of the man who had forged it – Leonardo da Vinci (1452-1519) and the body belonged to somebody else. Whether or not the face was his, it is clear that it is not proof of the existence of miracles or Jesus. It is hard to believe that Leo would have created such a bad forgery but then again it is good in the sense that it appears to be so baffling and was even more so in the past and that was what was important to him. And the objection of many that Leonardo never hinted that he was making a Shroud is silly for he couldn’t say if he was. If Leonardo didn’t make the Shroud maybe an associate of his did behind his back.

The book says the Shroud is a kind of photograph and explains that Leonardo had the knowledge and ability and motive to make it. What helps support the view that Leonardo created the Shroud is that many of his paintings were created without using drawings on the surface he was painting on as guidance. He had the genius to paint the Shroud and the skill to paint without leaving brushmarks. But it seems the Shroud could be a crude photograph.

The authors made an image like the Shroud image and it is admitted even by critics that the chemical solution the book says Leonardo used to make the snap could have been available to Leonardo (www.unisa.ac.za/dept/press/dearte/52/shroud2.html How Leonardo Did not Fake the Shroud of Turin, Nicholas Legh Allen). But they think the formula was not likely to have been used even if somebody was making photos in the middle ages. This is silly for it is like somebody finding a photograph allegedly from the thirteenth century and dismissing it as a forgery just because photography was not invented until the 19th century. The truth is we only think photography was first invented then and if we ignore the photo we could be ignoring the thing that proves us wrong. We know Leonardo read ancient texts about photosensitive chemicals. He designed camera obscuras and it has been found (Nicholas Allen) that a tower in Fontanellato in Italy could have been used by Leonardo to make the Shroud for it works like a camera and would capture an image on the Shroud if the right chemicals were deployed with the help of sunlight.
Photography could have been invented before the 19th century because the images it made like the Shroud were too vague and nobody, apart from an unusual few, was that interested in it. Plus the Church would have seen it as alchemy which was forbidden under grave penalties.
Some object that Leonardo needed to look like a Jew and have his face beaten to a pulp to make the image. But this ignores the fact that he would have used a bust not his actual face to put his face on the image. Leonardo could not have directly used his own face to make the picture for that would entail sitting a long time and being burned to a crisp by the sun. The book contains a picture that reveals that Leonardo and the Shroud man were dead ringers and both had long hair and strong beards. You don’t have to be a Jew to look like a Jew.
The claim of many believers that the Shroud man’s nose was broken is a lie. There is no evidence and many experts say as much. And if his nose was broken then how do you know it was broken during the Passion? It may have been misshapen from an earlier injury. Yet this lie about the broken nose is used by many to ridicule the hypothesis that the face of the Shroud man is Leonardo da Vinci who was possibly the creator of the Shroud. They jeer, “So we are supposed to believe that Leonardo had his nose broken to make the Shroud?” As we said, Leonardo was an artist and could have used materials to make his face or the bust with his face look injured.

Nicholas Allen has produced cloths exactly like the Shroud of Turin. When they are all shown in the negative you can see huge blotches and variations in shading in the background. This effect also appears in the Turin Shroud. If the Shroud were a miracle this would not be happening for God would not need or desire that effect. Worse if he did then why does the background not capture the image of the stone or whatever Jesus was laid out on? Allen used materials and devices that were certainly available in medieval times. His work then is better than that of Picknett and Prince in that respect.
It has been demonstrated beyond doubt that even in 1280 AD it was possible to make a photograph on linen to make the Shroud. Using a plaster cast of Jesus and silver nitrate solution and ammonia solution (human or animal urine will do) on linen which contains chemicals itself that can help form an image plus a plain old magnifying glass or a natural quartz crystal with the same ability can form a Shroud image with the help of a very strong sun and it helps a lot of the cast is painted white (www.petech.ac.za/shroud/is the.htm). You need a cast for the process is slow. The fact that the sun would have been used to provide the light source for making the Shroud is betrayed by the fact that the Shroud man’s body parts that are prominent are the brightest for the sun would reflect off them the most. This has been tested in experiments and faint yellow images that are in the negative and which rest on the upper fibres of the linen cloth have been made thus replicating the features of the Turin Shroud and showing it is no miracle. It is better to believe that some medieval genius stumbled on the secret of photography than to hold the Shroud up as a miracle for the first is naturally possible. When the Shroud is a photo it cannot be the image of Jesus at all because photography could not go back to his day. The medieval alchemists who experimented in everything could have developed some crude form of photography.
The Shroud created by Nicholas Allen matches the claims made for the Turin Shroud, that there is no pigment or dye used, that there is no sign of directionality, heat and water don’t harm the image, the image sits just on the top of the fibres of the cloth and does not penetrate and shows up best in the negative image and is very subtle in the positive image.
There are other ways to explain the image - photography is possible but there are other equally good and even better theories.

Lourdes etc
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