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The oldest of six children of a part-Jewish German family that had emigrated to the United States in 1849, Stieglitz spent his youth in a comfortable milieu that placed unusual emphasis on education, culture, and attainment.

Taken to Germany in 1881 to complete his education, he enrolled in a course in photochemistry. Stieglitz had a fascination with the role of light and with the replication possibilities of photography, as well as an understanding of how to organise forms to express emotion.

Infatuated with younger women, Stielglitz married Emmeline Obermeyer in 1893 and had one child, Kitty, in 1898. Allowances from Emmeline's father and his own, financed their living. Stieglitz divorced his wife Emmeline in 1918, who had thrown him out of their house when she came home and found him photographing O'Keeffe, with whom he moved in shortly thereafter. The two married in 1924 and were both successful, he as a photographer and art impresario, she as an artist who had received notoriety from Stieglitz at 291 (an art gallery in New York from 1905 to 1917) in 1916 and 1917. The marriage between O'Keeffe and Stieglitz was strained as she had to care more for his health due to a prevailing heart condition and his hypochondria. Following a visit to Santa Fe and Taos in 1929, O'Keeffe began to spend a portion of most summers in New Mexico.

Read more: Alfred Stieglitz

Ansel Adams (1902–1984) was the only child of very wealthy parents.

His parents were also relatively old – his mother was forty when he was born. Adams was brought up in a conservative environment in a massive house located in the middle of the Golden Gate, San Francisco, California.

When Adams was just four years old, the aftershock of an earthquake flung him against a brick wall in his backyard, breaking his nose (which remained crooked thereafter). Then, when Adams was five, a recession wiped out his family's fortunes. His father, Charles Hitchcock Adams, spent the rest of his life trying, unsuccessfully, to recover what they had lost. His wife nagged him day in and day out but he bore it all. He was also a very supportive parent to Adams.

Adams was a shy, erratic and intense child who did not have much success at school. He was pulled out of school in 1915 to be tutored at home. He later joined a private school, where he studied up to the eighth grade.

Read more: Ansel Adams – The Last American Landscape Photography Genius

Harold Eugene Edgerton was born in 1903 in Fremont, Nebraska. That indispensable enhancement device that it is built into your camera – the flash – is courtesy of Edgerton.

Edgerton had a brilliant mind; always thinking, always exploring, always devising. In 1920, he was an electrical engineering student at MIT (Massachusetts Institute of Technology), where he studied and predicted the behaviour of motors. Throwing a large volume of light into a motor made it easier to see the motor movements. This light was produced by a strobe: a heavy apparatus (about 60 pounds in those times) that contained a mercury-filled tube and could give a bright flash.Edgerton began thinking and concluded that the strobe could do much more than verify motor movements; it could see the speed at which things moved and capture the movement in a camera. He became a tireless marketer of the strobe and would continually visit engineering and vehicle companies to show them how it worked. 

Read more: A flash of inspiration

It can be hard to keep up with all the advances in printing technology - both in commercial printing and in desktop printing. The history of printing began as an attempt to reduce the cost of reproducing multiple copies of documents, fabrics, wall paper, etc... Printing smoothed the process of communication, and contributed to the development of commerce, law, religion and culture.

Read more: A brief history of printing