Like Muybridge, he gained significant fame for his photographs of Yosemite National Park, including Moon and Half Dome. With Willard Van Dyke and Edward Weston, he founded Group f/64, named after the smallest common aperture setting of cameras at the time. He also developed a method to determine the optimum exposure for a negative, known as the Zone System, enabling him to create tremendous detail within small gradation of shade in black-and-white photography.