Studio photography became easier to accomplish in the 1930s due to advances in lens technology and film speed. Celluloid film replaced glass plates in this period, and the quality improved, and the ISO increased progressively over the next 20 years.
During the Great Depression in the 1930s, documentary photography reached its zenith in the United States. Photographers no longer worked in studios; they went out into the field to capture images of common people. A growing interest in photojournalism and popular magazines like Life and Look coincided with the work of federal agency photographers.
During the 1930s, San Marcos Daily Record captured amazing studio portraits of people posing in front of mirrors.