To see with a keener eye has been a human obsession since the times of Leeuwenhoek and Galileo, considered fathers of the microscope and telescope, respectively. For centuries keener vision meant to see more clearly what was far away or what was very small—to magnify and sharpen. But in the 20th century it also came to signify all sorts of vision that once would have been deemed "magic"—the penetration of veils both around us and within us as well as the registering of forms of "light" to which human sight is utterly blind.