IMAX Dome Theater
Climb to the summit of the world's highest mountain ranges, travel back in time to the age of the dinosaurs, go boldly where no man has gone before, all from your seat in the J.L. Bedsole IMAX Dome Theater.
IMAX is derived from the phrase "maximum image." Through state-of-the-art IMAX technology, moviegoers are granted a unique perspective as larger-than-life images sweep above and around the 177 seats.
While the majority of IMAX theaters have huge, flat screens that more closely resemble commercial (35) mm screens, the 60-foot domed screen in the J.L. Bedsole Theater the only domed screen on the Gulf Coast wraps around the audience, immersing them in the center of the action.
The theater is lined with acoustic deadening material so that the only sound the audience hears comes from an array of digital speakers behind the domed screen.
The huge IMAX projector is operated in the glassed lobby area beneath the theater, visible from the lobby of the Gulf Coast Exploreum Science Center. The film is loaded and then the projector is raised by elevator into a compact "doghouse" in the middle of the theater's seating area.
The domed screen is made of perforated aluminum panels and is approximately 60 feet in diameter. The panels are perforated so the speakers and air conditioning can be mounted behind the screen. In the popular "pre-show," the house lights are turned off and the lights behind the dome are lit so that theater-goers can view the entire structure of the dome, including the speakers.
IMAX projection systems use the largest film frame in motion picture history, the 70 mm 15 perforation format, which is 10 times larger than conventional 35 mm film.
The IMAX film format is roughly the size of a card from a deck of playing cards. In comparison, standard 35 mm motion picture film has only four perforations per frame and is roughly the size of a postage stamp.
An average IMAX movie runs 45- 50 minutes and the reel of film is nearly 3 miles in length. The film travels through the projector at a rate of 5 1/2 feet per second.
The film advances through the projector horizontally in a wave-like action referred to as a "Rolling Loop" film movement. An Academy award-winning breakthrough in cinematography, it is the key to superior picture sharpness and steadiness.
The film reels, called platters, can be seen from the theater lobby. It takes one reel to feed the film into the projector, one to retrieve the film and a third for upcoming movie trailers. Platters are 52' in diameter the size of a truck tire.
The IMAX projector is more than 6 feet tall and weighs more than 2200 pounds.
IMAX developed a "rolling loop" system that uses air to advance the film past the projection lens without tearing the film. The film moves horizontally in a wave-like action similar to the motion that an inchworm uses to move along a sidewalk.
An Academy award-winning breakthrough in cinematography, the "rolling loop" method is the key to superior picture sharpness and steadiness.
The light is mounted on the top of the projector and supplies the illumination for the film image. It is a 15,000-watt xenon arc lamp that is 18.5 inches long and 4.5 inches in diameter. This light, if positioned properly, could be seen from the surface of the moon. It has a brighter intensity than the sun as viewed from the Earth.
Because the bulb can reach 1300 degrees Fahrenheit, an elaborate cooling system must move water and air around it whenever the projector is operating. Projectionists changing a lamp must wear ballistic safety gear in case the extremely high-pressure cooling system explodes.
Each lamp costs $6500 and lasts about three months.
The sound system is designed and built in Birmingham, Ala., by Sonics Associates, a company that produces sound systems for IMAX theaters worldwide. The IMAX/Sonics sound system uses 44 speakers, including 6 clusters of 6 speakers each, plus 8 sub-bass speakers.
The J.L. Bedsole IMAX Dome Theater's sound system was the first DVD-based digital sound system installed in a theater. It is capable of producing 12,000 watts of undistorted sound. This allows the audience to be surrounded with crystal clear sound.
You would have to line up 140 100-watt boom boxes to equal the power of the IMAX DVD audio system.
There is not a bad seat in the house. There are 177 specially designed seats in the theater. Each row of seats reclines at a different angle so that each viewer's focus is aimed at the center of the domed screen.