Scene: A close-up of a man's hands, his fingers pressing buttons on a video camera. Cut to a face creased in perplexity. Then a wide shot, revealing a classroom and a teacher...
I'm at the Adventure Film Academy, a fixture at the annual Kendal Mountain Festival since 2002, and the man at the front is BBC cameraman Mark Batey. Over three days, he'll explain everything from aperture to access law. He starts with the basics, but as Batey warns us: "You'll have to be comfortable hanging off a crag on a rope while holding a camera still."
The academy was founded by climber Brian Hall, a veteran of several Bond films and safety consultant on mountaineering docu-drama Touching the Void. Cheaper digital cameras and easy, online distribution has set off an avalanche of extreme-sports films but only the best rise to the top; Hall's academy equips novices with the skills to plan, shoot and edit them.
There are three categories of adventure film, says Hall: "Home or holiday movies: in one two-year period we got 16 ice-climbing movies, which are fascinating... if you're into ice-climbing. 'Outdoor porn' – looks fantastic, means nothing and destined to play in the background of a bar in Chamonix. Then there are movies with a story. These are rare, and the only adventure films with a wider appeal." The very best, such as Riding Giants – Stacy Peralta's paean to surfing culture, which opened the 2004 Sundance film festival – join the mainstream.
Day one starts with Batey's masterclass on framing. Zoom should be used sparingly; panning is banned: there's enough to think about with the camera still. Instead we learn to plan a sequence of shots that can be edited together to tell a story. As Richard Else, the producer of BBC Scotland's The Adventure Show, tells us, "I always plan a film from the point of view of a viewer. An editor sees the film 15 to 20 times, the viewer just once. The best films are simple, clear and direct."
Aspiring film-makers should be careful what they wish for, however. Paul Diffley spent 10 years working in IT before a moment of clarity at Banff Mountain Festival prompted him to jack in the day job. In 2006, he filmed Dave MacLeod pitting his fingernails against Rhapsody, the world's toughest rock-climbing route. The result: an award-winning film, called E11, that Joe Simpson of Touching the Void fame described as, "An alarming insight into the utterly obsessive psyche of world-class climbers." Diffley can forget early retirement, however: measure his income against hours worked and he earns less than the minimum wage. "But it's been a richer life than IT," he says. "I've spent a lot of time outdoors, witnessed some amazing climbing and met some great people." And done some hard work, too: on a recent shoot, Diffley's pack weighed 35kg, loaded up with camera, batteries and cables plus his climbing kit, ropes and harness. "Which would be all right, if I didn't have to walk up a mountain," he smiles.
For more on Kendal Mountain Festival: mountainfest.co.uk. The AFA course costs £80 per day or £250 for five days. The writer stayed at Plumtree House (plumtreehouse.co.uk)