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Capturing it on Film

film icon How do the experts capture avalanches on film, and live to try again?

Below are the basic steps that cinematographer Steve Kroschel uses. (Please don't try this yourself.)

Promising avalanche zone Scout the location
Kroschel consults with avalanche safety experts Doug Fessler and Jill Fredston to find a promising avalanche zone—an area that has been known to slide in the past. He also needs a location where the light will enable him to capture a dramatic shot, and a sunny day. For this shot Kroschel has chosen an isolated stretch of the Chugach mountain range in Alaska.
Preparing the explosives Prepare the trigger
When the weather looks promising, Doug, Jill and Steve fly to the site in a helicopter. Now begins a carefully choreographed sequence of events which will allow the team to predict exactly when the avalanche will slide, when the camera will turn on to capture the slide on film, and where they will be to avoid being captured themselves. First Doug and Jill prepare the explosives which will set off the avalanche. The bombs have fuses on them so that once they are lit, the team has just 90 seconds before the avalanche slides.
Prepping the camera in the crash box Put camera in crash box
The camera is housed inside a 60-pound crash box with foam padding stuffed around it to prevent the camera from breaking apart while the avalanche flows around it. The heavy crash box keeps the camera from being flattened once the snow comes to a stop. Inside the crash box is an avalanche transceiver, which enables the team to locate the box even if it winds up 12 feet under.
Setting the rat trap and timer Set rat trap and egg timer
Because film is expensive, Steve has come up with a low-tech but effective way to turn the camera on and off at the right time. An egg timer is attached, using string and duct tape, to a rat trap, which in turn is attached with string to a toggle switch on the camera. When the egg timer hits 15 minutes, the rat strap snaps, the toggle switch flips, the camera turns on, and film starts rolling. To stop the film rolling at the right moment, Steve runs the cables for the camera's battery around the outside of the crash box; as soon as the avalanche buries the box, the cables are disconnected, and the camera automatically turns off.
Preparing to toss bundle of dynamite out of helicopter window, on time cue Commence bombing mission
Steve relocates to another ridge with a second camera, in order to capture another angle of the avalanche on film. Meanwhile, Doug and Jill have just a few minutes to take to the skies and commence their carefully timed bombing mission. There's only one chance to get this shot. Jill wears two watches, one set to the egg timer, and another set to the explosives fuses. The fuses are lit so that the bombs will explode about 30 seconds after Steve's egg timer has activated the rat trap and started film rolling through the camera.
Searching for the crash box Locate crash box
The avalanche takes less than a minute to slide. Jill and Doug then take a second pass in the helicopter over the avalanche path, and set off additional explosives if they feel there is any chance there might still be some snow ready to slide. The team then returns to the avalanche zone, and uses the transceiver to locate the crash box, which is usually buried under enormous piles of hard, compacted snow. Once they know the general location of the crash box, they use long skinny poles called avalanche probes to poke through the snow and find the box.

Process Film
The film is sent to a lab to be processed. Click the first box below to see this avalanche. Click the other boxes to see more avalanches.

You'll need the free RealPlayer plugin to be able to view the avalanche clips below. If you already have the software, choose an appropriate connection speed to view a clip.

helicopter Helicopter Over Avalanche
house House Destroyed by Avalanche
speed Head-on Avalanche
top Avalanche on Peak
wide Massive Avalanche
Oh no Avalanche Crashes Down Slope

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