Long before his death last year, at the age of ninety-two, Ellsworth Kelly had secured a place for himself in the pantheon of American art. The list of major museums that do not hold his work in their collections is miniscule, and the edifice of his achievements—capped by the National Medal of Arts, awarded to him by President Barack Obama, in 2012—looms above artists of a certain stripe like an aesthetic El Capitan. But while his exuberantly colored shaped canvases, which sent ripples of influence across Minimalism, Pop art, and beyond, are familiar to almost everyone with a passing knowledge of postwar art history, his photographs—from which many of these iconic canvases draw their inspiration—remain almost completely unknown.