[geeks] I haven't gotten into this yet but I need some advice

[David Cantrell]

On Fri, Apr 12, 2002 at 03:46:22PM -0400, Joshua D Boyd wrote:

> Yes, film duplication looses data.  I thought that modern films were supposed
> to last.

Yes, they're supposed to.  I won't trust $media for my archives until it
has been tested.  Hard disks, provided you go with good quality disks, are
known to be reliable for the period the manufacturers say they are.  CD-Rs
and films are not *known* to be reliable cos they haven't existed long
enough to be tested for real.

>          I have a lot of extremely old 8mm film in good condition, maintaining
> what I'm guessing is the original image quality, and it spent a significant 
> amount of time in bad environments (attic, non-climate controlled storage
> locker, etc).  By extremely old, I really only mean 30+ years, not century. 

It probably looks good, but I doubt it'll be as good as it was originally.
SOME moisture will have got in, SOME microbeasties will be chewing their
way across the frames, ...

> If you go bad far enough, the film wasn't at all chemically stable, which I'm
> sure you know.  Kodak has been heard saying that their current film will 
> easily last 100+ years.

Can I wait a hundred years and get back to you on that? :-)

> > The archivals people did some tests with CD-Rs.  They're crap.  They also
> > take up a great deal more cubic inches per gigabyte than hard disks.  But
> > I'm talking about archiving stuff for the next century, not for the next
> > decade.
> 
> Well, I doubt that Mrs. Weiss really cares about the next century, although I'm
> sure she cares about 30+ years from now at a minimum.

Yes, we have kinda veered off the topic :-)  Having said that, if she wants
her great-grand-children to be able to laugh at the video of their grandfather
at their age (ooh look at those quaint clothes! and what's that metal thing?
a car? why doesn't it fly? bored now, want to go play with my jet boots) then
she could well want to archive for half a century or more.

> If we really are talking about data for the next century or 3, then we really
> should probably be talking metal, stone, and paper.

If you want your archive to maintain itself without being touched by people
then metal or stone, yes.  If you are willing to devote a small staff to it,
to do things like transfer from $medium_of_the_last_decade to $medium_of_
the_decade, then I'd still go with some kind of digital storage system, and
for *this* year's medium, I'd choose hard disks.

>                                                      Paper would be the most
> convienient, but care needs to be taken to use the right materials.  Archiving
> video to paper is easy enough, although you will loose a lot of dynamic range.

Errm, paper has more dynamic range than most video.  Especially if you're
talking monochrome.

> Just print a frame per page.  Including the audio is a bit trickier.  Perhaps
> raw PCM in hex, but will people remeber what PCM is?

That's a very good point.  We have similar problems with the written word -
just you look at two hundred year old handwriting.  It's unreadable apart
from to specialists.  Even one hundred year old writing is difficult to
follow.  Go back a thousand years, to something like the Anglo-Saxon
Chronicles, and it takes a good long time before you can even tell that
they're using our alphabet.  The skills required to read those are rare
indeed.

-- 
Grand Inquisitor Reverend David Cantrell | http://www.cantrell.org.uk/david

  While researching this email, I was forced to carry out some investigative
  work which unfortunately involved a bucket of puppies and a belt sander
    -- after JoeB, in the Monastery