Why an Atheist Thinks the Shroud of Turin is the Real Deal

Raking Light

By shining a beam of light from very close to the cloth, almost parallel to the surface, the ridges in the twill become very pronounced. The light exaggerates highlights and shadows. You can see the effect with a bright flashlight and a pair of denim jeans. You may also notice on the jeans, otherwise unnoticed wrinkles and creases become quite visible, as well. This use of near-parallel lighting, called raking light, is a valuable technique in the forensic examination of fabrics and other rough surfaces. Raking light is also used in the restoration of paintings to enable a restorer to more clearly see the exact nature of the artist’s brushstrokes.  

No brushstrokes were found in the images on the shroud, but creases and wrinkles were easily detected. It’s the nature of linen to wrinkle and retain creases. The flax fibers that are twisted together to form linen thread or yarn, like all plant fibers, is a cellulose material, a polymer made up of long chains of molecules of carbon, oxygen and hydrogen atoms. They form up in long strands, side by side but staggered, bound together by hydrogen bonds and thus forming long fibers. When linen is wet with water, the water molecules (H₂O) destabilize some of the existing bonds, but not enough of them to significantly weaken the fibers. When the cloth is allowed to dry, and the water molecules evaporate into the air, new bonds form but not always where they were before. This causes wrinkles and small creases. You can think of wrinkles as miniature rolling hills and creases as like jagged cliffs and deep gulches.  You don’t need to actually wet a piece of linen to create wrinkles and creases. Just increases followed by decreases in humidity levels is enough.