The IMAX experience


Oh we know Halloween is not here yet :), and no this is not a dress rehearsal. That's Vedaant in a 3D movie - his very first 3D experience - 'Toy Story 3' at bfi IMAX, London. Boy oh boy ! For the first few minutes, he was giggling, crouching, stretching out trying to grasp or fend objects, only to realise he could not really reach them - till he started to get the hang of the story.

Anyway, as I was saying, Watching a movie at IMAX is different ! They say, the screen is the largest screen in Britain. Have to say..its HUGE ! As tall as 4 Double-Decker buses!  

The show begins with an awesome sound and light show that showcases the excellent speaker system that practically engulfs you throughout the movie.

Some of those 'tornado' sounds that were demonstrated scared the living daylights out of us ..haha, and daddy's hand was big comfort. The day and night animation demo was really cool though.

Did you know?

How does a 3D film work ?

googling away...

A 3D film consists of two films being shown simultaneously. The 3D camera is simultaneously presenting one moving image to your left eye and another, slightly offset image, to your right eye.It has two lenses set the same distance apart as our eyes, and films both the left and the right eye images at the same time.
The more modern way to handle 3D uses polarized light. This technique makes use of a very weird property of light called polarization. Imagine two synchronized
projectors. One projector is showing the images of the movie intended for the left eye, while the other is projecting the images for the right eye. Both
projectors point at the same screen.

Now, in front of the lens of the left projector, we put a polarizing filter. The light coming through the projector has light waves oriented in both up-down and left-right directions. But the filter only lets through the light waves with the up-down orientation. We put another polarizing filter on the right projector that lets through only the light waves with the left-right orientation.

And to complete the system, we have everyone in the audience wear glasses that also contain two polarized filters. So, the left eye can see only the light coming from the left projector, and the right eye can see only the light from the right projector. The brain puts the two separate images together and creates the 3D effect.

 The two pictures are then projected through polarized glass, each eye polarized differently so that the left eye does not see the image of the right eye and vice versa. The viewer wears polarized glasses to help keep the two images separate.
Your brain then converges the two images and the magic is complete - the picture is within arm's reach!

IMAX Technology

The key to the IMAX experience is cinema's largest film frame, being projected by the world's most sophisticated projector onto a huge screen that encompasses the viewer's peripheral vision.

IMAX Projector

The IMAX projector is the most advanced, precise and powerful projector system in the world! The filmmakers who developed the IMAX system, started by using multiple cameras and multiple
projectors to create that 'in the picture' sensation. There was no single camera or projection system available to provide the image with the clarity and size that was required, so they searched for a new system that would enable them to deliver the experience without the joins. They developed a system called 15perf/70mm, the height of the film being 70mm and the width 15 perforations wide.

Each frame of film is rolled onto registration pins over special optical glass called field flattener. The film is then held in place, flat against the glass, by a vacuum whilst the image is projected on the screen. This system keeps the film perfectly still, further enhancing the illusion that you are really there.

The projector's patented shutter mechanism additionally transmits one-third more light than the shutter in conventional
projectors. The lamps used in the projector are 15, 000 watt xenon arc lamps that are water-cooled.

IMAX Sound System

The sound system is also larger than life. In order to support an image 20m high and 26m wide it needs to be! The Sonics system, specifically designed for IMAX theatres, eliminates variations in volume and sound quality over the theatre seating area. This allows all members of the audience to experience superb sound quality regardless of where they may be seated.

Six tracks of sound are sent to 6 large cluster speakers - 4 behind the screen, 1 to the rear left and 1 to the rear right behind the audience. There is also a huge bass speaker located behind the screen. 11, 600 watts of power wrap the audience in a crystal clear world of sound that completes the marriage with the image on screen. The digital soundtrack is loaded from a DVD disk onto a computer, which locks the projector and soundtrack together and controls the show. This system is called Digital Theatre Audio Control, or DTAC.

IMAX Cameras

IMAX Cameras, an integral part of the IMAX system, are extremely versatile and for each special situation IMAX designers and engineers have had to come up with innovative solutions.

The IMAX film format is so large that the film canisters in the IMAX camera can only hold 3 minutes of film at a time. This means you can shoot a scene for three minutes and then you have to stop and reload the camera. Reloading the camera takes approximately 30 minutes!


1 comment:

  1. Shekhar MahantaOctober 07, 2010

    Aha ! Have seen some 15 odd 3D movies, but now I know how it all works :-) . Very cool . Keep it up.