In 1973 Evans began to work with the innovative Polaroid SX-70 camera and an unlimited supply of film from its manufacturer. The virtues of the camera, introduced in 1972, fit perfectly with Evans's search for a concise yet poetic vision of his world: its instant prints were for the infirm seventy-year-old photographer what scissors and cut paper were for the aging Matisse. The unique SX-70 prints are the artist's last photographs, the culmination of half a century of work in photography. With the new camera, Evans returned to several of his themes—among the most important of which are signs, posters, and their ultimate reduction, the letter forms themselves. In the 1930s he had been the first American artist to draw emphatic attention to the impact of the sign in the landscape. His continuing interest in quoting the written language of commercial signs and translating them into self-sufficient pictures was fueled by his literary ambitions and by his understanding that the essential "stuff" of the contemporary world was to be found in these often unconscious symbols of modern life.