This training video is about IMAX 1570 projector being threaded from point of view. Projector load training POV …Made about twenty years ago. #imax #1570 #film #projector #training #behindthescenes #projector #largeformat #imaxexplained
I never realised, until recently, that the sound was not on the film. Amazing that a digital sound system can synch with a basic "analogue" film. Can it ever go out of synch? I mean - if there's a film breakage & the repairs & splicing results in losing a few frames, how does it get back in synch?
Hi, yes the entire sound system relies on frame count of the film. If the frames are not replaced after a crash the sound sync will be out. When ever a crash occurs resulting with damaged film, that damage must be accounted for and replaced with generally black frames by counting frame lines or sprockets holes. If the repair is large in terms of frames, this will become noticeable on screen. Depending on the severity, the film may need a replacement real. Replacing with black slugs can be very difficult to get right, a reference frame line near the damage in the film has to be found. As the film runs through the projector, a small electro/mechanical spinning wheel with optical sensors mechanically attached inside the projector sends pulses to the sound system. These pulses represent the frames of the film. So physically the film frame count from start frame to last must be maintained.
