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Forum URL: http://www.eyrie-productions.com/Forum/dcboard.cgi
Forum Name: Undocumented Features General
Topic ID: 22
Message ID: 32
#32, RE: JJ Concordet and marketable voices
Posted by Polychrome on Jun-14-01 at 02:26 AM
In response to message #31
>>>IMAX doesn't run at a higher framerate, your probably thinking of
>>>Showscan, which I believe uses a smaller flavor of 65mm (5 perf or 8
>>>perf) or VistaVision (35mm film shot sideways and 8 perfs wide, double
>>>the image area of regular 35mm motion picture film) at something like
>>>60 frames per second. IMAX runs at 24 frames per second, but the
>>>extreme size of each frame means a lot more space is taken up by less
>>>frames, hence the time limit. The IMAX film Titanica was 90
>>>minutes, but there was an intermission while they changed reels.
>>
>>You may be right, I don't remember - but I was pretty sure it ran at a
>>higher rate, on different film. It may have been the same material,
>>but the wheels are, what, two and a half feet across and four inches
>>wide?
>
>Well, it's 70mm wide, so whatever that translates to, I don't have a
>conversion table handy. :) I suppose they could make wider platters
>to take a bigger roll of film, but a 45 minute reel at 24fps weighs in
>at 200 pounds, and I imagine there is a weight limit for the platter
>system, and in what the projectionist may have to lug around at any
>given point.

Acetate weighs that much? Shit, no wonder we use polyester, Not even Pearl Harbor weighs 200 lbs.

>
>They might have used a polyester based print stock instead of acetate
>or something like that for durability, given how long an IMAX feature
>can run in the same theater (and how expensive prints are to make).

Almost assuredly. We don't get anything but polyester.

>We had a few 35mm prints come in printed on that when I was a
>projectionist, and while they were a little lighter they were a pain
>in the ass because they built up static electricity really fast when
>it was dry out and, as we were warned, the film would break the metal
>bits of the projector head before breaking itself if there was a
>problem and it got jammed because the tensile strength of the stuff
>was so high. They were also thinner than normal film, and the

Um, you must have some cheapass projectors man, when our film and projectors decide to have a fight, the film loses, usually getting stretched. Unfortunately our failsafes are designed to deal with *breaks*.

But here's how you get a long IMAX movie: sequential interlock. Theaters have two projectors for 3D right instead of running both at the same time you have a cue at the end of each "reel" to start the other projector and the film continues without stopping. Give each projector a quintiple platter tree and you can run for 6 hours without stopping. 6 hours of IMAX. Can you say sensory overload?

Polychrome