For two and a half months in 2010, during every hour the Museum of Modern Art was open, performance artist Marina Abramovic sat silently facing a chair filled by a steady stream of visitors. Photographer Marco Anelli was there with her, capturing the thoughtful, blank and tearful faces of each participant as they engaged in a wordless exchange with the artist. (Anelli’s ‘Portraits in the Presence of Marina Abramovic is at Chelsea’s Danziger Projects through Oct 27th).