Why do porous objects (wood, textile, hair, etc) appear darker when wet then when dry? A googling gave me this ("surface reflection and refraction"), but that doesn't sound entirely reasonable, as it merely talks of light being scattered, but the light in question is already diffuse. This also gives some suggestions, but nothing conclusive. Any chem/physics MeFiers know this?
posted on Dec 12, 2003 - 7 answers