The IMAX "ultimate film experience" combines a variety of technological innovations: special cameras, special projectors, giant screens, and footage shot on 70mm negative stock. Consider the following...
Our IMAX motion picture projection system, invented and developed by Imax Corporation, is the finest motion picture projection system in the world. Images of unsurpassed size, clarity, and impact, enhanced by a superb specially-designed six-channel, multi-speaker sound system, are projected onto our giant rectangular screen which is eight stories wide (84 feet) and six stories tall (62 feet). Our IMAX Theatre is the largest IMAX Theatre in the State of Michigan having the capability to show both 2D and 3D IMAX films. Seating capacity is 440 for 2D, 410 for 3D, and is fully handicapped accessible in accordance with ADA regulations.
The IMAX film frame is ten times larger than a conventional 35mm film frame, and three times larger than a standard 70mm film frame. It is horizontally oriented, and has a surface area of 5.5 square inches. The sheer size of an IMAX film frame, combined with the unique IMAX rolling-loop projection technology, is the key to the extraordinary sharpness and clarity of IMAX films. The film is Kodak ESTAR-base motion picture stock, and is strong enough to tow a car. The film is projected at the rate of 24 frames per second, and passes through the projector at the rate of 330 feet per minute or 5.5 feet per second. A typical 40-minute 2D IMAX film print is comprised of about 57,000 film frames, and if out-stretched, would span a distance of about 2.5 miles.
Sound is critical to the IMAX Experience. The six-channel, discrete digital IMAX motion picture sound system, with sub-bass, is manufactured by SONICS Associates Inc., a subsidiary of Imax Corporation, and is a world leader in sound system design and installation. The SONICS Proportional Point Source loudspeaker system, specifically designed for IMAX theatres, eliminates variations in volume and sound quality over the entire theatre seating area. This allows all members of the audience to experience superb sound quality regardless of where they may be seated.
It is power not volume, which provides the audience with life-like sound emitting from six speaker clusters and one sub-bass unit. The sub-bass unit comprises eight, eighteen-inch diameter woofers fully enclosed in a fiberglass insulated cabinet. Sounds as soft as a breeze can be heard along with crashing waves in our true-to-form surround sound environment. Sixteen amplifiers of low, mid, and high frequencies provide over 12,000 watts of power to the one and a half tons of speakers in the theatre. Low frequency sounds are so deep, that they are literally felt more than they are heard!
The lamphouse on top of the IMAX projector utilizes two 15,000-watt liquid-cooled, short-arc xenon lamps. The lamps weigh 10 pounds each, and are nearly two feet in length. Costing more than $6,000 each, the lamps have a life expectancy of only about 1,200 hours of operation and are replaced 4 times per year. Because of the extreme high-pressure xenon gas inside the quartz glass envelope of the lamp, projectionists must wear ballistic safety gear when changing out a lamp. If dropped, the xenon lamp would explode with the destructive force of a hand grenade.
The average luminance of one of these xenon lamps is approximately 1.6 billion candles per square yard--about equal to that of the Sun as viewed from the Earth's surface! The lamp has a light output of approximately 600,000 lumens. NASA uses this same type of lamp at the Kennedy Space Center to illuminate the Space Shuttle at night on the launching pad.
During normal operation, the clear quartz glass envelope of the lamp has a surface temperature of about 1,300 degrees. To prevent the lamp from overheating, it has coolant "jackets" that allow cool distilled water to be pumped around the electrodes at the flow rate of 8 gallons per minute and a pressure rate of 100 psi. In addition, an exhaust fan removes 1,200 cubic feet of air per minute from the lamphouse. The xenon lamps operate at 37.5 volts DC, and 400 amperes of current.
The million-dollar IMAX projector is the most advanced, highest-precision, and most powerful projector ever built. About the size of a Volkswagen Beetle, the key to its superior performance and reliability is the unique "Rolling Loop" film movement. The Rolling Loop advances the film horizontally in a smooth, wave-like motion. During projection, each film frame is positioned on fixed registration pins, and the film is held firmly against the rear element of the lens by a vacuum. As a result, picture and focus steadiness are far above conventional 35mm projection standards and provide outstanding image clarity on the giant IMAX screen.
IMAX film prints are projected and rewound from large 50-pound platters made of solid magnesium. These platters are 1/4 inch thick and 4.5 feet in diameter. They are harmonically balanced, and can support up to one hour of film weighing well over 400 pounds. The five platters are operated from a reel unit, separate of the projector. Four platters are used simultaneously to project one 3D IMAX film.
Following every IMAX Theatre presentation, guests are directed up to the third floor of the IMAX Theatre where they can get a behind-the-scenes glimpse of our entire projection system operation. The rear wall of the projection room features floor-to-ceiling windows which allow guests to view the projectionist operate and reload the film into the projector. A short recorded narration explains in brief the entire process.
|For more information about IMAX theatres and films, see the IMAX web site .