Ars Technica: Scientists unlock the chemical secrets of a 19th-century photography technique

Ars Technica: Scientists unlock the chemical secrets of a 19th-century photography technique. “Mordançage is a photographic process that yields striking black-and-white photographs characterized by ghostly veiling effects. Scientists from George Mason University have recently figured out precisely what is happening chemically during the process, according to a recent paper in Analytical Chemistry.”