Artist Piet Mondrian's paintings are instantly recognizable icons of 20th-century abstract painting. Their simplicity is deceptive. When Mondrian fled Europe for New York City just before World War II, he brought 17 paintings, most completed. Once in the U.S., Mondrian reworked those paintings. The full, dramatic extent of those revisions was recently revealed when Ron Spronk, a conservator and art historian at Harvard University, and his colleague Harry Cooper turned high-tech optical instruments on the canvases. Using methods such as X-radiology, infrared reflectography, examination under ultraviolet light, and cutting edge digital imaging, they were able to shed a new, intimate light on Mondrian's creative process. Spronk discussed how his use of technology revealed the secrets of artistic creation.