To earn money, he worked as a photoengraver, an activity he taught himself, first at Sahm& Co. printing house in 1920 than at Artes Gráficas Büxenstein in 1925.
In 1928 he met Siliava Sulamith, his first wife, an acting student and legal secretary to Hans Litten a well-known leftist lawyer.
Reuter wanted the publisher to print something to protest the event, passing a petition, but his efforts got him fired and blacklisted from further work.
He returned to Berlin in 1931 and bought a 6x9 Contessa Nettel camera and constructed his own enlarger, with the idea of selling the photographs for money.
[3][1] He worked with lawyer Hans Litten and leftist organizations to photograph life for Berlin's poor against the rising Nazi party.
[1][3] He made a living photographing wealthy families and tourists along the country's southern coast and connected with intellectuals such as Federico Garcia Lorca.
[3][6] The threesome's travels around Andalucía are partially documented by the German artist Jan Kurzke in his memoir The Good Comrade.
[7] When the Spanish Civil War broke out in 1936, he sent his wife and young son to France, while he joined the Republican forces against Francisco Franco.
[3][2] In this endeavour, he worked with Robert Capa and David Seymour, with the group called the Brigada Internacional de la Fotografía.
[5] Working with state agencies, he first created “The timeless world of the Indians”, traveling through Veracruz and in 1946 in Oaxaca with Juan Rulfo and the Papaloapan project in 1950.
[5] Although not an artist in the classic sense, in 1986, the Museo de Arte Moderno held a retrospective of his work, focusing on images of the indigenous and ballet scenes.
[8] In 2012 his work was exhibited other photographers such as Manuel Álvarez Bravo, Henri Cartier-Bresson, and Hugo Brehme at the Museo de Arte Moderno.