Peering Under Vermeers Without Peeling Off the Paint

High-tech scanning techniques used by geologists, planetary scientists, drug companies and the military are revealing secrets of how artists created their masterpieces.

WASHINGTON — Here is a question that art experts at the National Gallery of Art are trying to tackle: Are a couple of paintings in the museum’s collection that are credited to Johannes Vermeer actually the work of Vermeer, the 17th-century Dutch artist noted for his detailed, realistic portrayals of middle-class life? The two paintings are not obvious fakes. Indeed, one is considered a masterpiece, but they are unusual in the oeuvre of Vermeer: smaller than his other works, and painted on wooden panels instead of canvas. “And so they seem to be somewhat different from the rest of his work,” said Melanie Gifford, a research conservator at the National Gallery.