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How IMAX Works


Making an IMAX Film
Movie poster for "T-REX"
Movie poster for "T-REX"
Photo courtesy IMAX

Watching an IMAX film is an amazing experience, but the process of creating an IMAX film is even more amazing. For a variety of reasons, IMAX film production is much more complex than normal film production. To understand the process, we spoke to Michael Lewis of L-Squared Entertainment, who co-produced "T-REX" and produced and financed "Siegfried and Roy," two popular IMAX 3-D films.

Movie poster for "The Magic Box"
Movie poster for "The Magic Box"
Photo courtesy IMAX

Both of these films are especially interesting from a production standpoint. Not only are the films shot on IMAX's 15/70 film stock, but they are also shot in 3-D and make extensive use of computer-generated (CG) effects.

Because of the screen size and incredible detail on an IMAX image, the quality of computer-generated effects must be perfect to work on an IMAX screen. For example, the dinosaurs in "T-REX" have five times the detail of the dinosaurs in the "Jurassic Park" movies. This means that it takes five times more computer power to render each "T-REX" image, and five times the storage space.

According to Lewis, one of the key challenges when making any IMAX film has to do with the film size. The size of the film means three things to a director:

  • The camera is immense. It weighs 240 pounds (109 kg), so it requires special supports and rigging to move it around. A typical 35-mm movie camera, by comparison, weighs only 40 pounds (18 kg).
  • The size of the film means that the camera can hold only a three-minute spool, and it takes 20 minutes to reload.
  • The incredible detail available with a film size this large means that everything about the shot must be perfect, and each image must be stunning. The audience sees every flaw, and a lackluster image totally wastes the potential of the IMAX medium.

According to Lewis, "The cost and complexity in every segment of physical production is an order of magnitude greater with IMAX." In addition, "There are only two IMAX 3-D cameras in the world, so if you have a breakdown, you are standing around spending $100,000 a day on production costs."

An IMAX camera and crew at a movie shoot
An IMAX camera and crew at a movie shoot
Photo courtesy IMAX

On a normal film, 10 setups a day is normal. With IMAX, "Three or four a day is moving at lightspeed", according to Lewis. The camera is also very noisy -- it sounds like a chain saw when it is running. Actors and crew are all affected by the noise. In "Siegfried and Roy," the animals also reacted to the noise. All of the audio has to be done in post-production because of the camera's noise on the set.

Animals react to the noise and excitement at movie shoots.
Animals react to the noise and excitement at movie shoots.
Photo courtesy IMAX

The screen size and clarity mean that every frame of an IMAX film must be perfect. "In 35 millimeter, you can use lots of cheats in visual effects -- things like rain and darkness," says Michael Lewis. "In IMAX you see everything, and everything is photo-real. There are 100+ IMAX screens in museums, so things must be as accurate as possible. With a dinosaur, you have to worry about things like nostril slant and tooth decay. When placing a dinosaur on the ground, the eye instantly knows if something is not perfect."

The technical challenges mean that an IMAX film, which is normally just 40 or 50 minutes long, costs just as much to make as a normal film for theatrical release. For example, the "T-REX" film took five months for a feasibility study to prepare for filming, 40 days for the shoot and then 12 to 13 months to complete the film in post-production. The CG effects and dinosaurs consumed approximately 4 terabytes of disk space.

A typical IMAX film's production costs fall somewhere in the range of $3 million to $8 million for a 2-D feature, and $8 million to $15 million for 3-D, with 3-D films involving CG running at the high end of the scale. Films can either be funded by IMAX or self-funded by studios like Michael Lewis' L-Squared Entertainment.

Despite the challenges, the unique experience of the IMAX theater makes IMAX films a compelling medium for directors. With the number of theaters increasing worldwide, and with a rapidly growing audience for the IMAX experience, it is likely that a wide variety of films will be created for this venue in the years to come.

For more information on IMAX and related topics, check out the links on the next page.