235
VIDEO PRESERVES: ARCHIVING VIDEO TAPES
Note: Archiving DVDs is part of the booklet
"DVDs and
Interactive Video", that comes free with my 4th ed. of
Today's Video. Now for archiving video tape:
Cherished moments on videotape: we make them
first, then
we try to make them last. Through this magic ribbon
called
videotape, we can laugh at ourselves as infants,
remember the
sweet joy of Grandpa's smile, or record the antics
of our
children to show to their children. All over the
world family
histories are being archived, but some of these
priceless tapes
will not survive. The laws of physics and the
ravages of time
and environment all conspire to transform our
pretty pictures and
sound into bands of snow and wavy lines. We cannot
break the
laws of physics but we can mitigate against many
of tape's
enemies: heat, humidity, magnetism, dirt, pressure,
shock, and
poor recording practices.
Not an archival medium -
Let's get the bad news over with: videotape is not an
archival medium. Videotapes made thirty years
ago are barely
playable, even in the tender, loving hands of
an experienced
technician. Common videotapes recorded and played
back on common
VCRs by common nontechnical people, may last about
15 years.
There are some unknowns in this estimate; tape is made better
than it used to be. It may last longer than 15
years but we
won't know until enough time goes by to see how
it survives.
Most experts agree, however, that tape cannot endure generation
after generation like slides and photographs do.
More bad news: The videotape is not your big problem, your
VCR is. Video recorders change over the years,
each type
incompatible with the format that came before.
Think back to your super 8 movies. Do you still have a
projector to play them on? Those of you with long
gray whiskers
may remember regular 8 movies. Those projectors
are so old that
nobody makes parts for them, so you'd better treat
them like the
precious antiques that they are. And remember
Great Grandma's
stereopticon, a 3-D viewer to display postcard-like
photos?
No matter what method you use to record your magnetic
memories, you will have a hard time finding a
machine to play
them on twenty or thirty years from now. If you
record your
children on VHS, you may want to buy a "spare"
VCR and keep it in
mint condition along with your tapes. And if it
does break
thirty years from now, there surely won't be parts
for it.
Hopefully, someone somewhere will have a VHS machine that works.
Copying is no solution-
You paid $700 for that Betamax video recording of your
wedding 15 years ago. The original tapes were
edited down to a
beautiful 30 minute masterpiece (second generation)
which was
copied (third generation) to share with your friends.
Since
there are not many Betamaxes around, you figure
it might be wise
to copy your beta tape over onto a VHS tape (fourth
generation,
if you do it from a copy). Fifteen years from
now, when VHS VCRs
are rare, maybe you'll find an old one and duplicate
your VHS
tape onto your new digital videodisk recorder
(fifth generation).
What do you suppose you'll see? Most likely mush. Your
grandchildren will wonder why you made a tape
of penguins
mumbling in a snowstorm and titled it "Our
Wedding."
Eighteen Do's and Don'ts of Tape Care -
Okay, you took all that bad news pretty well. Fortunately,
there are some things you can do to preserve your
tape treasures.
1. Don't store your tape in a hot place such as
the dashboard of
your car on a sunny day, or atop a heating radiator.
The
cassette shell will warp and shrivel up like bacon.
2. Do keep your tape in a dry place. Tapes enjoy the same
temperature and humidity that people do. Leaving
a tape in a
damp basement will cause it to absorb moisture.
Mildew may even
grow inside the cassette, instantly causing head
clogs. Also,
high humidity promotes binder hydrolysis causing
the tape to act
sticky.
3. Don't play the tape in a malfunctioning VCR.
When a VCR
"eats" a tape, that part of your tape
will be gone for good.
4. Don't store tapes near electromagnetic fields like those
around electric motors, high intensity lamp bases,
televisions,
computers, power transformers, and loudspeakers.
Leaving your
tapes lying atop your TV set will slowly erase
them.
5. Don't place your cassettes on a carpet or slide
their boxes
around on a carpet. Carpets create copious static
electricity
which attracts dust, just the thing your videocassette
doesn't
want.
6. Do keep videotapes away from small children. Sticky, curious
fingers can deposit head-clogging oils on the
tape, or cause
folds and bumps in the tape. Goodness knows what
teething saliva
does to a videocassette.
7. Do keep the temperature and humidity steady.
Wide
environmental swings cause the tape to expand
and contract,
causing stresses that stretch the tape.
8. Do acclimate tapes before playing them. They
should be the
same temperature as the machine that plays them.
If you bring a
cold tape into a warm room, it will collect condensation
just
like a glass of iced tea. Seal the tape in a plastic
bag and let
it sit for a few hours and it will warm up while
staying dry.
This technique applies in the winter when you take your tape from
a cold car to the house, or in the summer when
you take your tape
from the air-conditioned indoors to the humid
outdoors; sealing
the tape keeps it dry.
9. Don't store your tape half played; it leaves
a bump in the
tape. Winding the tape to the beginning or end
will place the
bump harmlessly on the tape leader.
10. Store tapes upright rather than flat. Sometimes
the tape
winds or unwinds unevenly leaving tiny ridges
sticking out from
the roll. When the tape lies flat, those ridges
rub against the
sides of the cassette fraying them.
11. Do "exercise" tapes once every year or so by winding
them to
the end and rewinding them. This relaxes the tape,
reducing
stresses that build up over time. Before playing
a tape that
hasn't been played for years, also wind it to
the end and rewind
it to the beginning before you play it; the relaxed
tape is less
likely to exhibit flagwaving and tracking problems.
12. Do handle tapes gently. Banging cassettes
around will
damage exposed edges, affecting your sound or
tracking. Keep
precious tapes protected in hard, vinyl boxes,
the kinds used at
video rental stores. These will keep your cassettes
dust free,
and safe from being squashed.
13. Do make a copy at the first sign of tape degradation.
Although you go down one generation in quality, you may be able
to salvage the recording before the original tape
becomes totally
unplayable.
14. Do label your tapes lest you accidentally record "Mork
and
Mindy" reruns over Baby's first steps.
15. Do record important events on new, high-quality
videotape.
Although the words "high grade" does not guarantee that
the
videotape is superior, with a little reading and
experimentation,
you can settle on a brand and type of tape that
works well for
you.
16. Record important events at the standard play
(SP) mode.
Tapes recorded at the extended play (EP) speed have their
magnetism jammed too tightly together to yield
an optimal
picture. Also, age causes slow-playing tapes to
exhibit
flagwaving and mistracking. In addition, EP tapes
play poorly on
VCRs that are not perfectly adjusted.
17. Avoid the super thin, long-play tapes. Use
standard
thickness (T120, or their 120 minute HI8 counterparts)
to assure
that the tape will stretch the least amount.
18. When possible, use a super VHS or HI8 VCR with its
corresponding super tape to record the sharpest
and smoothest
picture.
No matter how well you care for your tape, the machine you
play it on is crucial. A well-maintained VCR will
treat your tape
gently and play it accurately. If you are really
planning to
keep a video archive for twenty years or more,
you may want to
purchase a good quality VCR and seal it in a cool,
dry time
capsule along with your tapes. Run the VCR a couple
times a year
just to exercise the rubber parts and distribute
the lubrication.
Select a tape machine with direct drive motors that don't have
rubber belts to dry out and slip or snap. And
if you are really
serious about archiving your videotape, ask your
local repairman
what parts you should buy (while they are still
available) to
place in the time capsule with your VCR.
TABLE 1
HOME VIDEOTAPE RECORDERS THROUGH THE AGES, NEARLY ALL
INCOMPATIBLE WITH EACH OTHER.
1956
See-Hear Home Video System - Announced by RCA
but was never
seen or heard of again.
1965 Ampex Signature VI VCR - Featured longitudinal recording
to
record 25 minutes of video on a reel of tape.
The 1/4"
tape moved at a whopping 100 inches per second.
Sony Consumer Video (CV) System - Reels of half-inch tape
stored a black-and-white picture. Using a "skip
field"
recording system, every other video picture was
skipped.
1969
Akai - Two systems using 1/4" tape on open
reels. One made
black-and-white, the other color recordings.
1971
Electron Video Recording - Video cartridge system
that
played back images on a TV set from film. It couldn't
record, just play.
1972
Cartrivision - Two reels of 1/2" tape were
stacked one on
top of the other in a clunky cassette roughly
the size of a
hardcover book. Also used "skip-field"
recording, but at
least it was in color.
U-Matic - Three-quarter inch tape inside a cassette the
size of a box of candy. This is the only "old"
format that
is still in use, although superseded by U-Matic
SP
(Superior Performance).
1975
Panasonic's Omnivision I - Housed a single reel
of tape in
a cartridge and wound the tape onto a take-up
reel inside
the transport. This meant that you could never
remove a
cassette in the middle of a program.
Betamax - Sony's color videocassette recorder
capable of
recording one hour. First popular home VCR.
1976
The Great Time Machine - Using the VX format invented
by
Matshusita, recorded 2 hours on 1/2" tape
in a cassette
that was a mechanical nightmare. Faye Dunaway
used a Great
Time Machine in the 1978 movie The Eyes of Laura
Mars.
1977
V-Cord I and V-Cord II - Black-and-white V-Cord
I stored 20
minutes of black-and-white tape in a cassette.
V-Cord II
added color and introduced a slower speed to extend
recording time and was one of the first formats
to offer
freeze frame and slow motion.
VHS - Introduced by JVC and Matshusita, put two
hours on a
tape. Throughout 1977, tape speed wars saw Beta
II counter
with a three hour tape, VHS followed with a four
hour
length, Beta III then offered five hours, and
VHS mopped up
the competition with six hour recording.
1978
VCR - Invented by the Dutch electronics giant
Philips.
They also invented the name VCR but could only register the
trademark in Europe. The name caught on much better
than
the machines which stacked one reel of tape above
the
other.
Video 2000 - Using 1/2" videotape, this Philips and Grundig
machine played 1/4" of the tape in one direction.
You would
then flip the tape over and play the other half
in the
other direction.
1980
8mm - Proffered by Sony and 127 other leading
consumer
electronics manufacturers. Introduced high density
recording on audiocassette-sized 8mm tape.
1982
Video Showcase - Japan's Funai joined forces with
Technicolor to create the compact videocassette
(CVC)
system, the lightest and most portable recording
system of
its time using 1/4" cassettes that could
record 30 minutes.
VHS-C - Miniature videocassette the size of a
deck of cards
that holds regular VHS tape that requires an adapter
to
play the miniscule tape in a regular VHS VCR.
1987
SVHS - JVC's improved VHS recording system made
a sharper
picture but required special tape. SVHS VCRs can
also
record and playback VHS tapes.
ED-Beta - Improved version of Betamax offered
by Sony to
outdo SVHS. A fine machine but too expensive.
1996
DV - Digital Video, available in $2000 - 3000
camcorders
and a few professional decks. Professional DVCAM
and
DVCPRO models can play consumer DV tapes, but
consumer
decks can not play the pro tapes.
What new, incompatible format will next year bring making
our tape libraries obsolete? Maybe HDTV videotape?
TABLE 2
HOW VIDEOTAPE WORKS (Or Doesn't Work)
Videotape is a plastic ribbon impregnated with a
magnetizable metal powder. Before recording, the
particles are
oriented randomly. During recording, the video
heads create
magnetism that orient the particles in certain
directions. Thus
video signals are converted into magnetic patterns
on the tape.
When the tape is played back, video heads again pass over the
magnetic powder and sense the magnetic vibrations
and convert
these vibrations back into a video signal.
Video signals consist of millions of electrical
vibrations
each second. Each vibrations represents a tiny
piece of your
picture. If you lose just one vibration for any
reason, you will
see a momentary speck on your screen rather than
the piece of
picture that belonged there. This momentary loss
of picture is
called a dropout.
Tiny particles of dust, dirt, smoke, loose powder from the
tape, or debris from the cassette housing can
get between the
spinning video heads and the magnetic coating,
losing the signal
for a moment. Dropouts also result when some of
the magnetic
surface flakes off the tape, taking a piece of
picture with it.
A fold or a scratch on the tape is a million times larger than
a
dust particle and can cause picture disruptions
lasting several
seconds. A scratch or fold along the length of
your tape could
ruin your whole program. Playing chewed-up tape
is also
hazardous to your heads. The delicate spinning
video heads could
snag on a "pothole" in the tape and
become chipped. You will see
a half snowy or totally snowy picture, and the
only cure will be
to replace the VCR heads, probably costing $35
for the heads and
$75 for the labor.
Less serious, but the symptoms are the same, are
clogged
video heads. Here dirt or shedding magnetic powder
jams itself
inside the tiny gap in the heads that senses the
magnetism. This
rather common condition can usually be cured by
playing a head
cleaning videocassette that, hopefully, wipes
away the dirt.
Hi fi sound is sometimes recorded along with the
video, and
it can drop out too. Normal, low fidelity sound
is recorded on a
linear track along the edge of the videotape.
Damage to the edge
of the tape can mangle this sound.
On the opposite edge of the tape is the control track, a
series of magnetic pulses that guide the spinning
video heads so
that they precisely follow the magnetic paths
on the tape (and
don't play between the paths). Damage to this
edge of the tape
will cause your picture to roll or mistrack; a
band of hash may
run across part of your picture.
Tape, being a long plastic ribbon, can contract
and stretch
depending on temperature, humidity, cassette tightness,
and
tightness of your rollers inside your VCR. When
the tape
stretches or contracts even a tiny amount, it
changes the
positions of the magnetic paths, making it hard
for the tape
heads to follow. This sometimes causes your picture
to jitter,
especially at the top, or to flagwave, flopping
back and forth at
the top. As the condition worsens, your picture
folds into
diagonal lines. Sometimes tape stretching causes
your video
player to mistrack, again causing a band of hash
to run across
part of your TV screen.
TABLE 3
MEASURING TAPE
Videotape is manufactured under exacting conditions. A
precise amount of magnetic powder is impregnated
into the tape
(or in the case of metal evaporated --- ME ---tape,
just the
right amount of metal is evaporated onto the tape).
The
particles of powder are small and are packed tightly
in a certain
orientation to maximize their magnetizability.
Greater magnetic density is one of the major differences
between the various grades of videotape. High
grade tape uses
smaller particles in a greater concentration than
normal grade
cassettes. This results in a smoother (less grainy)
picture and
a stronger retention of the magnetic patterns.
High grade tapes
often deliver truer colors, smoother pictures,
and better sound
than their normal grade brothers, even when recorded
at the
slower EP speed.
Super VHS and HI8 formulations pack the magnetic particles
even more densely, and use particles that hold
more magnetism,
resulting in sharper, smoother pictures than their
high grade
brothers. It takes a super VHS or HI8 VCR to record
on these
special tapes.
Although various tape formulations differ somewhat
in how
well they record hi fi sound, there is no such
thing as "hi fi"
videotape. Manufacturers just put the words on
the box to
improve sales.
The actual difference between the performance
of one
manufacturer's "hi grade" tape and other
manufacturer's "normal"
tape may be very small. It is hard to separate
the hype from the
facts when it comes to "hi grade" tape.
Even from batch to
batch, one manufacturer's tape may have some cassettes
that out
perform others. Although there are laboratory
tape tests
appearing in various video and consumer magazines,
the test don't
always take into account how the tapes will play
on your machine.
For instance, a tape that gives a very sharp picture on one
person's machine may yield a slightly grainy picture
on
another's. The best bet is to try several types
of name brand
videocassettes on your VCR and judge for yourself
which ones look
the best. Avoid the "off brand" and
"white box" cassettes found
at discount stores. Some may be okay, but they
are less reliable
than the major players such as Fuji, JVC, Panasonic,
Scotch (3M),
Sony, TDK, Denon, and Maxell.
TABLE 4
THE 8MM STORY
When 8mm and Hi8 mm tape first came out, it immediately
suffered a bad reputation, especially the metal
evaporated (ME)
formulations. There were stories of massive dropouts,
headclogs,
stretching, and the inability to stand up to the
rigors of
editing. Even to this day, some manufacturers
describe 8mm tape
as an "acquisition" medium (where the
tapes run through the
camcorder once while recording in the field),
rather than an
editing or archival medium (where the tapes are
shuttled back and
forth, still framed, rethreaded, and replayed
many times).
So what's the story today; can 8mm tape be trusted
with
your family memories?
According to several manufacturers I called, recent
8mm
tape formulations have surmounted all of the problems
experienced
in the early days. The magnetic surface has a
smoother, harder
protective covering, and the tape stock itself
is stronger and
less likely to stretch. All agreed, however, that
MP (metal
particle) tape is little hardier than its ME (metal
evaporated)
counterpart. ME affords better specs (stronger
signal retention,
higher signal-to-noise ratio, sharper pictures,
purer colors) but
may be too flimsy for editing. Sensing a niche,
Fuji has
introduced an "ME Position" tape that
has the high performance of
ME tape, but is really souped-up MP tape with
the durability of
MP tape.
Not trusting the manufacturers unconditionally,
I called a
couple heavy 8mm users to see if they had experienced
any
trouble.
Pat Navagato of Nova Video Productions in Harrisburg, VA,
who does a lot of industrial and wedding recordings
in Hi8 felt
that the format "performed much better than
the bandwagon of
negative publicity would lead you to believe."
On his Sony and
Fuji stock, he typically sees only 3 or 4 tiny
dropouts every 2
hour tape. His 4 year old ME and MP tapes still
play well,
although his ME tapes look better to him. Any
problems he's
seen, he attributes to his camcorder, feeling
that if you run the
tape through a clean, good quality, well-adjusted
camcorder, you
should get good results.
David Rapp of Custom Video Services in Reno, NV,
runs
thousands of Hi8 tapes through his editing and
film transfer
service each year. He recommends mastering on
8mm ME tape
because:
1. The high energy tape is harder to erase (thus
holds its
magnetism better).
2. Is small enough to conveniently archive in
a safe
deposit box.
3. Because Hi8 is a bit rare, his clients come
back to him
to make duplicates from the masters (no fool,
Dave).
Custom Video shoots and edits in Hi8 using ME
tape and "has
no problem with it holding up." He uses Sony
ME and Fuji M221E
(the new Fuji "ME Position" formula)
tape with a Sony V5000
camera and Sony CVD1000 source editing deck. He
too had some
trouble at first with 8mm, but attributes it to
the equipment,
not the tape. Contrary to popular opinion, Dave
feels that MP
tape has more dropouts than ME. As for longevity,
Dave's been
using Hi8 tape for 4 years and says "every
time I pull out an old
tape, it's fine."
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