Secondo Pia and photographic negative effect

The first photographic method was the daguerreotype which was introduced in 1839. Daguerreotype (daguerréotype) was the first publicly available photographic process; it was widely used during the 1840s and 1850s. “Daguerreotype” also refers to an image created through this process. Invented by Louis Daguerre and introduced worldwide in 1839, the daguerreotype was almost completely superseded …

Skeptics claim it is a forgery

A commonly held view of the Shroud of Turin is that is is a medieval forgery that originated around 1390 AD. “Today, the bulk of evidence indicates that the Shroud originated sometime around the Middle Ages, and was created by human hands.” https://www.discovermagazine.com/the-sciences/the-shroud-of-turin-created-by-miracle-or-medieval-forgers “The History of the Shroud of Turin begins in the year 1390 …

What is the Shroud of Turin? part 2/2

https://en.wikipedia.org/wiki/File:Shroudofturin.jpg The shroud is rectangular, measuring approximately 4.4 by 1.1 metres (14 ft 5 in × 3 ft 7 in). The cloth is woven in a three-to-one herringbone twill composed of flax fibrils. Its most distinctive characteristic is the faint, brownish image of a front and back view of a naked man with his hands …