Although Callahan had little formal training, he credited Ansel Adams, Alfred Stieglitz, and Edward Steichen as his inspirations for pursuing photography professionally. Callahan began teaching at Chicago’s Institute of Design in the fall of 1946. He would give his students various photographic assignments that he would then undertake himself. Throughout his career, he developed his so-called “technique of seeing,” which relied upon finding new ways to look at the world around him. This close-up image is a flattened view of the windows on a Chicago building’s façade, demonstrating Callahan’s interest in multiple exposures, visual rhythms, and the graphic effects of light and shadow.