At the age of fifteen Lebeck was drafted into the Wehrmacht and sent to the Eastern Front where he was captured as a POW by the Soviet Army. Finally repatriated after World War II, he finished high school at the Donaueschingen Fürstenberg Gymnasium, and went on to study ethnology in Zurich and New York. Self-taught as a photographer, he started in 1952 as a freelancer selling to various newspapers and magazines in Heidelberg. Lebeck then went on to be employed by the magazines Illustrierte wie Revue and Kristall, and finally by the German weekly news magazine Stern. He worked for Stern for thirty years as a photojournalist, with a brief sabbatical during 1977 to 1978, as editor-in-chief of the monthly educational magazine Geo. Since 2001 Lebeck has resided in Berlin.
Lebeck became well known in 1960 after his report on the independence of the Congo “Afrika im Jahre Null” (“Africa in Year Zero”) which included a photograph of an African boy, Ambroise Boimbo, standing beside the steel scabbard of Belgian King Baudouin. To this day that picture remains his “calling card”.