Video: Changing film at IMAX


Okay so at this point we are going to get the film out of the projector. And start prepping the next film.

Most important for every show we’ve got to give the projector a quick clean. So we’ll get that sorted now.

One of the main components of the projector is the rotor that you can see spinning around here at the moment. That’s part of our film transport system as well as the shutter mechanism, so it has got a dual purpose. The IMAX projector is also known as a rolling loop projector. And this is the area just in these little gaps just here and here where the rolling loop will form.

Okay so with IMAX 3D we have two films, a left eye film and a right eye film. Your left eye will only ever see the left film and your right eye will only ever see the right film.

We’re just checking our frame lines to make sure that we are in frame and the left and right eye are in sync with each other, which they are, so we are almost good to go. With two film paths we’ve got the right eye on the top and left eye on the bottom. As I said before, the right eye will only ever see the right film and the left eye will only ever see the left film. And in this area just here we can see why: this is an opening in the rotor where it lets the light out; in that same area above that‘s where a shutter is so it will only ever project one eye at a time. Then when there is a shutter in the bottom we have an opening in here for the light to be sent out through the lens at the front of the projector. So it always projects left eye right eye left eye right eye at 24 frames a second at the same rate as a regular cinema projector.

Okay at this point we are doing our final double check. And we can now put the projector in show position with just a few minutes to spare.

The sound played with an IMAX film isn’t actually on the film. It is separate. It is a digital sound track, uncompressed digital audio, so once you’ve got the film queued you can then lock the sound.

( IMAX movie session begins: “You can now put on your 3D glasses. Sit back and relax and enjoy the movie.”)

About this Video

David Booty, Senior Technical Advisort for IMAX Melbourne Museum, shows us what happens in the projection booth between shows.
Length: 4:07

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