by Gord Harris and Claude Richard, Imax Corporation

Getting to the Top - The Imax Lightweight Mark II Camera

What do you do when one of the most talented and experienced filmmakers asks for your help to film on top of Mount Everest? You jump at the chance and get busy!

Greg MacGillivray and David Breashears approached Imax with this challenge in the fall of 1994, after seeing a prototype Lightweight MKII camera at the International Space Theatre Consortium (ISTC). MacGillivray had used the regular Mk II camera since the early days of "To Fly!" (1976) and knew that the basic design was rugged and reliable, if heavy.

The Lightweight MkII was a result of a development program by Ken Stone, Kevin Kowalchuk and Stuart Macfarlane to put the camera on a crash diet. The flywheel was eliminated and magnesium body panels substituted for aluminum. Motors, materials and electronics were replaced with lighter, stronger designs. The team reviewed and machined every sub-assembly to trim grams of weight. Our target of 38lbs for a ready-to-shoot camera was achieved and a successful Steadicam test was shot that summer.

With the weight under control, the next challenge was to make the camera able to film under extreme duress. In the cold and oxygen-deprived conditions found at the top of Everest, even the simplest of tasks can be confusing and dangerous. Veteran mountaineer David Breashears specified that the camera had to be loadable at minus 40 degrees and had to operate easily for climbers wearing gloves whose senses were dulled by high altitude, brutal winds and fatigue. Furthermore, it had to operate without supplementary heaters or blimps.

In October 1994, we defined our engineering recommendations to MacGillivray Freeman Films for the summit camera. To ensure the camera ran freely at Everest temperatures, Ken Stone, Kevin Kowalchuk and John Harris worked together to reduce power draw by reworking movements to tolerate cold shrinkage. Stiff rubber belts, cables and lubricants were replaced with synthetic materials and NASA-rated greases that wouldn't freeze up, stiffen or shatter. Lenses were stripped down, re-lubed and re-collimated with a second focus index mark for the thin space-like 5 p.s.i. atmospheres. We even provided a hand crank for the camera like on old cars, to help free up the movement after a night of cold-soaking on the mountain!

After many cold chamber tests, Kevin Kowalchuk worked closely with David Breashears to add specific mountaineering and ergonomic refinements. Nylon web tie points and special handles were added on all faces, such that the camera could be loaded while literally suspended on climbing ropes. Magazine lids were hinged and safety tethers added to all parts so they would not be dropped or blown away in gale force winds.

Loading and operating controls were enlarged so they could be handled with gloves. Special nylon snow covers and plastic guards were put over metal parts to prevent freezing to moist human flesh like a tongue on a frozen iron post!

These changes were tested atop Mount Washington in the spring of 1995. Then the refined camera and gear went to Nepal with Kowalchuk as camera support for an initial test expedition. With only a few minor glitches, 30 rolls were shot. A thumbs up was given for an attempt at filming on the summit the following Spring. On May 23, 1996, David Breashears and expedition co-leader Ed Viesturs broached the 29,028-foot summit and shot four rolls of film flawlessly from the world's highest peak!

Extract from the Imax newsletter The IMAX Experience March , 98 issue.

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