On his website, young Dutch photographer Tom Janssen presents himself as a documentary photographer, but I would say that his work is slightly different from what we usually call that way. His images are wide scenes of urban (and sometimes natural) spaces, where slowly we detect something happening inside.
Groups of people gathered to watch something, the core of their attention often concelead from us: Janssen's images show the theatre where a photographer would normally move, looking for the right shots and the right angles, moving inside the people, choosing the good background and the captivating details, but perhaps ignoring the complexity of the whole scene. Janssen focuses exactly on that, and if I had to choose an example of what an engaged observation could be in photography, I would definitely choose his photographs.
All images © Tom Janssen