Librarians, archivists, and curators today meet unique challenges when facing huge numbers of photographs accumulated in their institutions. Coming to terms with these masses in a responsible way means to reflect on cataloguing and digitization standards able to record their (material) complexity. It also means to constantly justify a series of investments: in cataloguing and digitization projects, but also in storage space, restoration, archival and conservation materials, not to speak of human resources. It means, ultimately, to reflect on the systems of value that one decides to apply while dealing with these holdings: the dematerialization rhetoric that often goes hand-in-hand with digitization campaigns tends to increase their fragility, on the other side we are confronted more and more often with the ‘contemporary repackaging of erstwhile ephemeral and disposable photographic prints' that acquire a new ‘archival value’.1 In this short essay I will focus on these systems of value. My aim is to offer some methodological tools to deal with documentary photographs in art historical institutions. These instruments derive from the intersection of photographic and archival theories and practices that shaped my experience as Head of the Photothek at the Kunsthistorisches Institut in Florenz, Max Planck Institute, for more than a decade.