Re: [Leica] [Partly Relevant] The Economical Leica and Future Film

["Bryan Willman" <bryanwi@seanet.com>]

First, my few contacts in the movie industry tell
me that modern 35mm commercial stuff isn't
1/2 frame, but some sideways panamorphic thing.

Second, MPEG works fine for things like TV sets,
you couldn't possibly tolerate it for showing on
a commerical movie screen.  People shoot or
print up to 70mm (or even bigger for IMAX) because
*uncompressed* 35mm isn't *good enough* for
some big screen movies.  MPEG only helps for
small screen things.

Third, 7,776,000 megabytes is 7.7 terabytes,
which would be larger than, say, the Sabre airline
reservation system.  About 6 years ago, there were
thought to be at most 1/2 dozen database > 2TB in
the world.  I'm sure there are more now, disk grows
fast,  but make no mistake 7.7TB is a *BIG* system.

To pump movie data in and out of the machine fast
enough to allow real time editing, you need fast disks,
and lots of them.  So IDE drives don't cut it.
Effective price is about $100/GB.  7700 * $100 = about 
3/4 million $ in disks.  But to keep that much disk
running, you need hot backups (say, 1 for 3) and a
staff of several humans to run around and replace them.
Big bucks, even for a movie.)

And of course, you need, say, 10 times that much store
to edit down all the takes into the final story line.

BTW - it's very difficult to effectively back up or reload
a multi-terabyte database.  Archiving the stuff would
be quite hard.

And finally, if we concede 36MB per frame,
the 24fps data rate => 864mb/second, which
is faster than any PCI bus.  In fact, it's faster 
than all but the largest commercial system buses.
(It's faster then the main memory bandwidth of
 almost all current computers.)

So, in practice, there are no commercially viable
current computers that can edit *all* of the data
for a movie *on-line*.  Of course, it's easy to store
and edit this data as film.  (Toy-story was made
with a whole farm of computers, and took a long
time, and it's a *cartoon*, not a live action flick.)

So, people edit a much reduced and compressed
version on-line, and send an edit list out to an
edit-house that then edits the physical film.
Computer generated stuff is very good, but
very laborious, not real-time.

So, right now, film is more workable, cheaper, etc.

And it will be for a while.

For *Movies*.

TV is  a totally different ball game.

bmw



- ---Original Message-----
From: Patrick G. Sobalvarro <pgs@sobalvarro.org>
To: leica-users@mejac.palo-alto.ca.us <leica-users@mejac.palo-alto.ca.us>
Date: Saturday, May 23, 1998 1:58 PM
Subject: Re: [Leica] [Partly Relevant] The Economical Leica and Future Film


SNIP


>It may be the case that 35mm film will not disappear for an
>extra-special long time, but it won't be because the movie industry is
>supporting it to avoid the cost of digital storage for movies.  Let's do
>a little arithmetic here:
>
>2.5 hours * 3,600 seconds/hour * 24 frames/second = 216,000 frames in a
>movie.
>
>35mm movie film is what we would call half-frame, so each frame is good
>for at most 2K x 3K pixels (this is a generous estimate).  Assume we
>record 48 bits/pixel, or 16 bits/color channel.
>
>216,000 frames * 6,000,000 pixels/frame * 48 bits/pixel * 1 byte/8 bits
>= 7,776,000 megabytes.
>
>MPEG II compression rates are typically about 10 to 1, giving us 778
>gigabytes for the whole movie.  At today's consumer prices (what you get
>if you walk down to your consumer electronics store and buy an 8GB
>disk), disks cost about US$40/gigabyte, for a cost of about US$31,000
>for storing a movie at quite high resolution.
>
>Obviously for the entire movie's shooting you would need at least ten
>times that amount of storage, but even if it were 100 times it would be
>a small cost compared to that of making a feature film, and disk storage
>costs have in recent years followed an exponential decay curve,
>decreasing by a factor of two every 18 months or so.
>
>So it would be possible to build the equipment to do this sort of thing
>right now, except that development costs would be large and the
>potential market small.  Still, the parts cost is small enough that I
>would guess that within ten years most feature movies will be shot
>digitally.
>
>-Patrick
>