John Szarkowski, the longtime director of photography at the Museum of Modern Art in New York and a dominant figure in the establishment of photography as an art form, has died. He was 81.

Szarkowski, who began his career as a photographer and returned to his camera in recent years, died Saturday in Pittsfield, Mass., said Peter MacGill of the Pace/MacGill Gallery in New York. Szarkowski died of complications from a stroke he suffered in March.