I find titles the hardest thing. I was worried that 'Waste Land' was too much of a downer. For me, 'The Crash Reel' confronts what the film is about: it's not just about the reality of a crash, it's about the extremity we all face, and what happens when life crashes on you.

Why is nobody questioning the sanity or suicidal tendencies of Everest ascenders? It's kind of a question of framing: How do you frame these activities? We frame them as freedom-loving, exciting, progressing sports and they are. But there are other ways to frame it. It's also true that these young men, neurologists say that their frontal lobes aren't developed yet - the long-term planning part of the brain.

I don't believe in objectivity. I observe the observer's paradox every moment I'm filming. Your presence is changing everything; there's no mistaking it. And you have a responsibility.

Extreme sports tricks are becoming increasingly complex, the courses ever more challenging and crashes all too common.

With portable cameras and affordable data and non-linear digital editing, I think this is a golden age of documentary filmmaking. These new technologies mean we can make complicated, beautifully crafted and cinematic films about real-life stories.

There's a theory of accidents that I studied when I was making a film about nuclear weapons: you can never eliminate accidents, because the measures you introduce to prevent accidents actually produce more accidents. That's certainly true of this sport; you're flying over 40 feet of what might look like snow, but it's hard as ice, it's as hard as pavement. You're doing acrobatic spins and tricks, 40 feet above pavement, essentially. There's been more accidents since, and there are going to continue to be more accidents, that's the nature of the sport.

I love making fiction films as well as nonfiction ones, and hope to keep challenging myself to make better and better work.