We are so used to the white purity of ancient marble sculptures that we imagine the Greeks and Romans felt the same: certainly the artists and patrons of the Renaissance and later centuries believed that white was right. New research using strong raking light sources and beams of ultraviolet light has shown, however, that many Classical statues were gaudily painted in a plethora of colours.
“The ideal of unpainted sculpture took shape in Renaissance Rome, inspired by finds and early collections of Classical marble statues such as the Laocoön, discovered in 1506, said Dr Susanne Ebbinghaus of Harvard University, organiser of a recent conference on Gods in Colour. These were denuded of their painted surfaces by prolonged exposure to the elements, burial and often, most likely, a good scrub upon recovery.”
Not entirely a new thing but the "raking light" seems a new twist. It looks as if the technique shows differences in texture where different colors were placed(?).