Louis Daguerre worked with Joseph Niepce, developing the heliograph.
After Niepce's death, Daguerre invented the daguerreotype. It used mercury gas. The pictures it produced had to be viewed at an angle. The wet-plate process was developed from calotype. It created crisp images on glass plates with collodion. It was used to make the first photos of Egypt. Wet-plate was very difficult to travel with, however. The materials would freeze in cold climates, and boil in hot ones.
William Henry Jackson used wet-plate to photograph Yosemite and other national parks. Edward S. Curtis used it to document Native American culture.
Alfred Stieglitz, after studying engineering, studied photography in Berlin. One of his favorite subjects was New York cityscapes.
He was part of the "photo-secession", with Edward Steichen. He published Camera Work magazine. His salon, 291 Galleries, showed work by Rodan, Cézanne, and Picasso. He popularized the work of Georgia O'Keefe through his gallery.
Steichen joined the US Air Corps to protect France during World War II. Stieglitz went bankrupt and considered quitting photography. However, his correspondence with O'Keefe kept him going. Stieglitz and O'Keefe married later. After coming back from the war, Steichen was made curator for the Museum of Modern Art's "Family of Man" exhibit, which toured the world and was the basis for an art book.
The press is known as the "fourth estate." In the US, print isn't restricted, but TV and radio are.
Emmett Till was a black boy who was lynched for whistling at a white woman. Photos of the body were published in the black press.
The Students Non-violent Coordinating Committee is an anti-segregation group. They were victims of police brutality. This was not covered by the media, until the Birmingham riot. Photos of the riot caused difficulties for the US in foreign affairs.
Famous photos taken during this era include the burning monk Quang Duc, a Vietnamese policeman executing a suspect, napalm victims fleeing a village, and a girl crying over a student shot at Kent State.
Styles of modernist photography championed a sharp, crisp focus in the images and generally leaned toward realism in the images.