We sort of understand how painkillers work. You take one, and it reduces your headache. We don't understand how photographs work. And that, to me, is an essential problem as a practitioner.

My current project was shot on film, and because of that I've spent my entire day removing dust-specks from negatives. You wouldn't have to do that on digital because you don't get dust on the scanner. I say to myself, "Why am I doing this all day?" I could have just bought a digital camera and I wouldn't have to remove dust-specks ever again. But when you move closer to a film image, it has a real truth to it. And I really like that.

There is a danger in our modern practice of using embedded journalism. As there is less and less money available for journalism to uphold its independence, there is a temptation for people to take short cuts. If this army or that army or this corporation is willing to pay for your flight or your accommodation, then it's much more difficult to tell what the real story might be. I do have a concern about that.

Reading is always a way of forming a bond with other people. I'm not very good at socializing - I quite like spending time alone - so reading is a way of engaging quite deeply with the way other people think. Quite often when you meet other people socially you don't get to have a conversation of any depth. You end up talking about how well or how badly someone is doing at school or something of that sort. Questions like, "What we are," "Who we are," "Where are we going," you get those from literature and from people that spend some time thinking.

It's certainly important to include text beside documentary photographs. Furthermore, it's important to include text in a way that's useful and accessible.

There's an awful lot of work being done that no one ever sees, or that is only seen in the gallery world. I feel that the public are losing touch with the great stuff that's being done in photography.

Good photographs aren't just complex. They are enigmatic. Images are beguiling. And the way they play into our psychology, into our visual cortex, is something we still don't understand.