Karmen's documentary methods were both influential and controversial; his renowned technical ability captured the emotion of war and the repetition of key shots and framings between film projects became a hallmark, but he would often blur the lines of Cinéma vérité by restaging key battles, including the lifting of the siege of Leningrad ("Ленинград в борьбе", 1942), the Viet Minh victory at the siege of Dien Bien Phu ("Вьетнам", 1955), and the 1956 landing in Cuba of militants led by Fidel Castro, re-enacted as a first person documentary.