The origins of the shroud and its image are the subject of intense debate among scientists, theologians, historians and researchers. Some contend that the shroud is the cloth placed on the body of Jesus Christ at the time of his burial, and that the face image is the Holy Face of Jesus. Others contend that the artifact was created in the Middle Ages. The Catholic Church has neither formally endorsed nor rejected the shroud, but in 1958 Pope Pius XII approved of the image in association with the Roman Catholic devotion to the Holy Face of Jesus.
The image on the shroud is much clearer in black-and-white negative than in its natural sepia color. The negative image was first observed on the evening of May 28, 1898, on the reverse photographic plate of amateur photographer Secondo Pia, who was allowed to photograph it while it was being exhibited in the Turin Cathedral. In 1978 a detailed examination was carried out by a team of American scientists called STURP. It found no reliable evidences of forgery, and called the question of how the image was formed "a mystery".