Radiation and optical techniques in the visual examination of paintings

Employing highly sophisticated chemical, physical, and optical techniques, scientists analyze and even date materials in works of art. The art conservator, however, in his routine examination of a painting has at his disposal simple, nondestructive, visual methods for investigating its construction and the extent of deterioration and alteration. Using various kinds of visible radiation, low power stereoscopic magnification, uv, ir, and x rays, he may uncover evidence indicative of either a genuine or fraudulent provenance. Illustrations of successful applications of the techniques are given, but it is emphasized that often no information of immediate significance to authenticity is forthcoming.