On the contrary, the evidence is clear:
“Hence, the presence of these biological nanoparticles found during our experiments point to a violent death for the man wrapped in the Turin Shroud,” Fanti said.
Fanti says the latest discovery debunks the age-old claim that someone simply painted on the image of the shroud.
The characteristics of these nanoparticles “cannot be artifacts made over the centuries on the fabric of the Shroud,” he said.
The shroud is one of the most well-known relics associated with Christ, and researchers have poured over the haunting image of the crucified man who appears on it.
Researchers say the latest discovery was made possible because of new technology.
“These findings could only be revealed by the methods recently developed in the field of electron microscopy,” said Carlino. He said the research marked the first study of "the nanoscale properties of a pristine fiber taken from the Turin Shroud."
So, that is actual blood, not paint, on the Shroud.
Four plants on the shroud are significant because, as researchers Danin and Baruch report, “…the assemblage…occurs in only one rather small spot on earth, this being the Judean mountains and the Judean Desert of Israel, in the vicinity of Jerusalem.”
Read more at http://www.patheos.com/blogs/prayergardens/2014/04/flowers-of-the-shroud-of-turin/#14mPDXE4pp0TaoBd.99
And the plants found on the Shroud, are from Jerusalem.
So, the 15th century European artist went to a lot of trouble to make this authentic. He killed a man and painted his blood on the Shroud. Then collected flowers from Jerusalem and covered the Shroud in them.
If this were true, it should be possible to identify the pigments used by chemical analysis, just as conservators can do for the paintings of Old Masters. But the Sturp team found no evidence of any pigments or dyes on the cloth in sufficient amounts to explain the image. Nor are there any signs of it being rendered in brush strokes. In fact the image on the linen is barely visible to the naked eye, and wasn’t identified at all until 1898, when it became apparent in the negative image of a photograph taken by Secondo Pia, an amateur Italian photographer. The faint coloration of the flax fibres isn’t caused by any darker substance being laid on top or infused into them - it’s the very material of the fibres themselves that has darkened. And in contrast to most dyeing or painting methods, the colouring cannot be dissolved, bleached or altered by most standard chemical agents. The Sturp group asserted that the image is the real form of a “scourged, crucified man… not the product of an artist”. There are genuine bloodstains on the cloth, and we even know the blood group (AB, if you’re interested). There are traces of human DNA too, although it is badly degraded.
Not only that, but the 15th century artist used a technique that was never used before, or since.