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RE: First Film To Be Sent Via Satellite

Title: RE: First Film To Be Sent Via Satellite

A) This looks like a heck of a good idea.

B) Guesstimate calculations:

        (These are Big Screen estimates from my CineRama/Todd-AO days at Ampex many moons ago)

        Film width 70 mm (maybe 140mm)
        Frame Height: 35 mm
        Resultion at Film Plane: 100 line pairs/mm (could be higher)
        Frame rate: 30/sec

        Film length: 120 min or 7200 sec or 216,000 frames

        1 frame:
        100 lp/mm * 2 * 100 lp/mm * 2 = 40,000 pixels/mm^2
        Area: 70 mm x 35 mm = 1400 mm^2
        Pixels/frame = 40,000 x 1400 = 56,000,000 (probably high; the working area of film is less, don't have the manual handy)

        Bits/pixel = 40 to 64 (film has more dynamic range than TV or VGA!)
        Bits/frame = 64 * 56,000,000 = 2.24 Gb/s

        Data rate = 2.24 Gb/s * 30 frames/sec = 67.2 Gb/s.

        This is totally uncompressed. Video compression ratios of 10:1 to 100:1 are not uncommon. In particular the RGB color channels are usually sampled at only 1/2  the brightness channel because of reduced color spatial resolution of human bein's.

        At even 10:1 compression it would fit into an .ae channel with plenty left over for error checking/correction, blow-you-away sound. 1 wavelength in a DWDM fiber.

        Mini-DV takes about 272 Mb/sec (but is only NTSC resolution) Does not do well in a 100BASE-TX channel :(; hence FireWire.

        DVD (MPEG-2 compression) is 5-6 Mb/sec (turn on your DVD's Nerd-O-Meter), easily fits in a 10BASE-T channel. A DVD movie usually fits on a 9 Gb disk (1         side).

        If we agree to 6.7 Gb/sec then a movie would require 1.45 Terabits. Or maybe as little as 150 Gb, which can be had for $1500, trivial compared to a release print cost.. You would need some bodacious buffering, though! And the "highly compressed" bit would be to fit into satellite transponder channels. I would think it would be easier just to ship hard disks.

        From the numbers quoted below, it does not look like they are talking Cinerama-grade. 70mm release prints cost upwards of $10,000 in the late 1960's, for, say Mad, Mad, Mad, Mad World. And Philips 70 mm projectors (true mechanical works of art) cost a lot more than $35k. These babies could fill up a screen with 96ft chord length, used fluid cooling in the film projection gates, etc.

        Your Mileage May Vary!

        Fun speculations,

        Larry Miller