Contrast has always been appreciated as a significant factor in image quality, but it is less widely recognized that
it is a key factor in the representation of depth, solidity and three-dimensionality in images in general, and in
paintings in particular. This aspect of contrast was a key factor in the introduction of oil paint as a painting
medium at the beginning of the fifteenth century, as a practical means of contrast enhancement. However, recent
conservatorship efforts have established that the first oil paintings were not, as commonly supposed, by van Eyck
in Flanders in the 1430s, but by Masolino da Panicale in Italy in the 1420s. These developments led to the use of
chiaroscuro technique in various forms, all of which are techniques for enhanced shadowing.