This history of the relationship of Einstein and photography really begins with a young man named Erwin Finlay-Freundlich. Freundlich was an assistant at the Observatory in Berlin. After Einstein wrote an open call to astronomers to help verify his Theory of Relativity, Freundlich responded. Einstein needed someone to help prove his theory by photographing the sun and surrounding sky during the time of a total eclipse to prove that the light from the stars would bend around this large body and its gravitational field. The next total eclipse would be seen in 1914 in the Crimea in Russia. But his superiors at the Observatory were not interested in sponsoring such an expedition. Freundlich then turned to the Lick Observatory in America and William Wallace Campbell agreed to take up the challenge.
Campbell and Freundlich both led expeditions into Russian in 1914. Soon after arrival, Archduke Ferdinand was assassinated and this sparked World War I. Russian troops found Freundlich and his crew in Crimea, arrested him as a prisoner of war (as he was German) and confiscated his equipment. Campbell and his American crew,who were camped near Kiev, were allowed to continue the experiment, but the eclipse was clouded over and the trip was a failure. In 1917, after another eclipse photographed with substandard equipment (as his original equipment was left in Russia), Campbell declared Einstein's theory incorrect only to be contradicted by the photos taken by British Arthur Stanley Eddington in Africa in 1919.
Campbell was driven to get results. In 1921, he went to Australia to document this next eclipse. He was not the only expedition there, but was the only one to get firm results. His team examined the plates and the location of the stars compared with non-eclipse photos of the star patterns. The locations did indeed reveal that the light was bending around the sun and he had confirmed Einstein's theory with the use of photography.
1921 NY Times article
Linda Connor's photo of 1918 glass plate
Recent eclipse images
Partial article on Lick's Einstein
1922 Eclipse in Australia
William Wallace Campbell bio