Three views of the man of the shroud. (right) In the natural color photo, faint but observable blood stains the head and arms. The stains on the shroud indicate that blood flowed while the man was upright, but apparently the blood was not smeared when the man was wrapped in the shroud. Some of those who have studied the shroud argue that a miracle explains the phenomenon, but the author posits that a forger or 14th century artist has been caught in a simple error. (center) Brilliant colors highlight the enhanced photo of the man of the shroud. To produce the photo, scientists analyzed the density gradients of the images on the shroud and assigned a different color to each density level. (left) Contrast enhancement sharpens and defines the image on the shroud. The negative image on the actual shroud has been reversed here to a positive. Photographing the black-and-white original with color film produced the greenish tint.