While the 35 mm SLR camera had already appeared before the war, its major disadvantage was the waist-level finder which gave a laterally reversed image, taking away the immediacy between the photographer and his subject. In the Contax reflex, to be called the Contax S, a pentaprism was positioned directly above the focusing screen, which offered an eye-level, unreversed view of the viewfinder. This major technical advantage was critical in establishing the 35 mm SLR as the definitive camera type for the decades that followed.