In his second year of graduate school, Dane deQuilettes thought something was wrong with his microscope. He had just returned to the University of Washington from the University of Oxford, where he had learned to make perovskites—polycrystalline solar materials that can be printed like ink—and he was eager to see what the film would reveal. But the image looked wrong. He was convinced he had botched the calibration and spent days troubleshooting in secret. The microscope was fine. He discovered.