Lara and I have just returned from having seen "Salt of the Earth" at the Curzon in Bloomsbury. It was absolutely stunning. It commenced with a walk through of his early life as a farmer's son who got an education and went off to be an economist but, by a circuitous route, ended up giving up that career and starting from scratch as a photographer and, subsequently, social documentarist.
I haven't seen a more powerful film about not just a brave photographer but about how man treats man. "McCullin" is an incredibly strong movie but this, in my opinion, is epic.
Do whatever you need to do but I can't recommend too highly that we should all see "Salt of the Earth". Incidentally, whilst he makes various appearances with a DSLR, only the photos from the end of his Genesis project were actually shot in digital.