Recent scholarship on the history of German anthropology has tended to describe its trajectory between 1900 and the Nazi period as characterized by a paradigmatic shift from the liberal to the anti-humanistic. This article reconstructs key moments in the history of anthropometric photography between 1900 and 1925, paying particular attention to the role of the influential liberal anthropologist Rudolf Martin (1864–1925) in the standardization of anthropological method and technique. It is shown that Rudolf Martin’s primary significance was social and institutional. The article reconstructs key stages in Martin’s writing on and uses of photography and analyses the peculiar form of scientific debate surrounding the development of anthropometric photography, which centred on local and practical questions. Against the political backdrop of German colonialism in Africa and studies of prisoners of war during the First World War, two key tensions in this history surface: between anthropological method and its politicization, and between the international scientific ethos and nationalist impulses. By adopting a practical–epistemic perspective, the article also destabilizes the conventional differentiation between the German liberal and anti-humanist anthropological traditions. Finally, the article suggests that there is a certain historical irony in the fact that the liberal Martin was central in the process that endowed physical anthropology with prestige precisely in the period when major parts of German society increasingly came to view ‘race’ as offering powerful, scientific answers to social and political questions.