Movies tie things up in an arbitrary length of time, but I have always liked things that aren't fully realised.

Silent films were, I think, more different than we know to sound films. We think of it as simply that we added dialogue and in actual fact I think it was an entirely different art form.

Sixty-five days principle photography, five-day weeks, which is the only way I'll work. With my cinematographer Russell Boyd, we take as much time as possible before pre-production, looking at stills. The next most important thing: he will come to me and talk about lenses. And I'll see his plan, which is generally great, and I might talk about how the light will be, handheld or not? I talk very freely, and try not to talk specifically, just talk around it, because it can unlock all sorts of things.

There's almost a fear that if you understood too deeply the way you arrived at choices, you could become self-conscious. In any case, many ideas which are full of personal meaning seem rather banal when you put words to them.

Various studios are still shooting on film with digital grain and the DI negatives, it's not ideal. We should really be all film or all digital. But that being said, the old way of graining in the camera, now you can make changes like a painter. It's dangerous because you can ruin the film, you can over-fiddle. We've all seen films and gone 'what the hell is that?'

I've become wary of interviews in which you're forced to go back over the reasons why you made certain decisions. You tend to rationalize what you've done, to intellectually review a process that is often intuitive.

I think Ed Harris is a conscious screen actor, so I think it was strong, it was like he put everything together somehow in 'The Way Back'. He likes, I don't want to say the method approach, because that's not really necessarily his way of working, but it was easy to do because of the location. He'd go off by himself, and they would make things.