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Venturing
From The VCR
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Written
By George Avgerakis
As
our industry shifts from a tape-analog to computer-digital,
the issue most concerning us is reliability. When
we put a videocassette into a VCR, we can be 99% sure
video would play on the monitor. In terms of executing
the mission, we never really gave much thought to
the reliability of the VCR system.
Today,
we hear the term, "mission critical," derived
from NASA's traditional philosophy guarding the safety
of its human payloads. To achieve "mission critical,"
reliability, NASA used "tridundant" design.
Instead of a redundancy, the doubling of every critical
piece of equipment, tridundancy dictates that you
triple every piece! And still, astronauts died.
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Reading over
my article, "Are You Mission Critical" (Feb. 1997),
I realized that mission criticality implies not only to efforts
of manufacturers, but of end users as well. So what can we do
to make our computer based systems mission critical?
I for one,
do not have the financial capability of building a tridundant
NLE-animation platform, but recently, I have begun retooling for
redundant backup at about double the cost of the basic configuration.
Here are some basics I have been exploring. If you'd like to contribute
your own, email them to me and I will incorporate them in a larger
article later.
Before beginning
nonlinear editing or animation, you've got to have a reliable
boot drive. Mine is constantly getting corrupted, requiring reinstallations
of the operating system (after reformating). So I bought two,
1 gigabyte drives, and installed DOS, Windows95, WindowsNT 3.51
and 4.0 in separate partitions on each. Then I installed all my
programs. Now, if my system drive gets corrupted in the middle
of the job, I can switch to the backup system drive and continue
working without delay.
Then I found
two programs that make the job enormously easier; Partition Magic
and Drive Copy from PowerQuest Corporation. Partition Magic ($69.95)
allows you to build and change partition structures after data
is on a drive, without risking the data. Drive Copy ($29.95) allows
you to copy one drive to another of equal or greater size, including
the operating system! No more hour long Windows 95 disk installs!
Employing these two programs, I can obtain tridundancy by having
a third system drive backed up on an Iomega Jaz disk.
The next flakiest
part of a system is the high speed SCSI media drives. I hear you
crying already, "I've just got enough drives to hold enough
video for the length of shows I create. Now I've got to buy twice
that?" Yes, but maybe not right away.
Consider the
role of the VCR in NLE work. If you're like me, you usually set
all of your renderings to be executed overnight and then arrive
in the morning to see your final work. AT THAT MOMENT, back up
your show to videotape, the highest grade you've got. I use my
BetaSP deck.
Like you,
I've been stretching my linear systems out another year because
I can't, yet, totally rely on computers. Now JVC offers a straddle
position that can, if you act quickly, be cost free.
JVC's newly
repriced S-Digital VCRs offer transparent dubbing from all formats.
Their BR-75U editing recorder ($9,000), costs about what you could
get for your BetaSP deck. JVC's BR85U, at $16,000, with pre-read,
eliminates two of the three machines in your edit suite, an even
sweeter deal.
Now, you can
back up your NLE projects to 4:2:2 digital tape at run time, and,
if need be, re-acquire the project at no loss. Or, if your NLE
system goes down for good, use your one old analog VCR as a source
and edit linear digital!
Finally, consider
building redundancy into the NLE drives with a Redundant Array
of Independent Drives or RAID. A RAID is a complete dupe of your
current drive array. Continuously, the RAID imitates every operation
you execute on the editing drives. If one of your primary drives
dies, the RAID instantaneously kicks in and informs you in case
you want to replace it, without shutting down the computer.
In setting
up a RAID, get used to housing your primary drives in a separate
enclosure. This is a good idea even if you don't add a RAID, because
a) the drives add a lot of heat to your CPU enclosure, and b)
the drives should have their own power supply because the standard
250 watts in most workstations was never intended to power three
9 gig drives.
And how about
considering backup power supplies? A redundant 110v. power supply
should be included in your drive enclosure. But what happens if
you have a blackout? This common emergency requires a battery-powered
backup, or UPS (Uninterrupted Power Supply). The UPS connects
to your house current remaining continually charged. Whenever
the current fails, the UPS cuts in so fast, the computer never
notices. An alarm gives you enough time to save your data before
the batteries die.
Obviously,
this article could be longer and more detailed, but let me leave
you with an interesting anecdote Richard Shope, one of the NASA
engineers who built the Mars Pathfinder probe. When I asked how
NASA budgeted so many new projects, Mr. Shope informed me that
the tridundancy philosophy has been set aside for a new operational
philosophy best described as, "Good, Fast and Cheap."
Sound familiar?
GFAC design
says that instead of one billion dollar, tridundant probe, we
design three 330 million dollar, nonredundant, all-or-nothing
probes. Oddly, NASA found that by ditching the tridundancy, they
could actually send ten times as many probes. Trouble is, with
the American Public and Congress being so hypercritical, one failure
tends to jeopardize the entire budget anyway. Now aren't you glad
that video production isn't rocket science?
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