CARING FOR YOUR HOME VIDEO TAPE
Since the late
1950s, video has served as a powerful medium of artistic expression
and visual documentation, capturing and portraying events that shape
our lives and our perception of the world. Today, video camcorders
are used frequently to document momentous events in the life of a
family - the birth of a child, high school graduation, summer
vacations, and weddings.
Unfortunately, as an information storage medium, videotape is not as
stable as photographs. Videotape is a fragile medium subject to
damage and deterioration from exposure to poor environmental
conditions and inadequate handling practices. Even if properly cared
for, magnetic tape may last only for a few decades.
composed primarily of three components:
magnetic (metal oxide) particles, a polyurethane-based binder, and a
polyester base material.
The metal oxide
particles record and store magnetic signals. Magnetic particles
differ greatly in their stability. Changes in the magnetic
properties of these materials may result in an irretrievable loss of
color, saturation, and sound clarity. Iron oxide and cobalt-modified
iron oxide particles are the most stable of the commonly available
magnetic materials used in videotapes. These materials are generally
found in most grades of commonly available non-professional
binder holds the magnetic particles in place. Often the binder also
contains special lubricants to smooth passage of the tape across the
recording and playback devices. The binder is subject to a type of
chemical deterioration known as hydrolysis. In this process, long
polymeric molecules are broken apart by a reaction with water to
produce shorter and less mechanically stable molecules. As a result,
the videotape becomes sticky and soft - magnetic particles may shed
from the base (referred to as sticky shed syndrome) and clog
recording heads. Playback is impossible.
The polyester base
material provides a flexible support. In itself the base is
chemically stable. However, the polyester base is susceptible to
physical deformations due to excessive tape pack stresses and poor
wind quality. These deformations can result in mistracking when the
tape is played. A back coating, if present, reduces static
electricity and aids in keeping the tape securely wound when in
storage. The back coat also serves to reduce tape friction and helps
prevent tape distortion by providing a more uniform tape pack wind.
All components are
subject to irreversible deterioration caused by exposure to extremes
of temperature and humidity as well as physical damage due to poor
handling and storage practices.
The best way to
prevent deterioration is to store all videotapes in an environment
that does not fluctuate significantly in temperature or relative
humidity. High temperature, high humidity, and the presence of dust
and pollutants in the air will result in irreversible loss of both
video and audio signals.
temperature and humidity controlled environment - 68 degrees F and
20-30% relative humidity is recommended for the safe home storage of
videotapes in a hot, wet environment. Do not expose them to direct
sunlight, which will cause them to heat up and will warp the reels
or cassette housing. Storage at high temperatures (in an attic or on
windowsills) may result in tape-to-tape adhesion (known as
blocking), degradation of the binder (known as shedding), and
permanent distortion of the tape backing. Such degradations can lead
to severe image deterioration known as dropouts. In video
recordings, short-duration dropouts appear as flashes, white spots,
or streaks. Storage at high humidity (in a basement or garage) may
cause fungal growth.
handling at all times. Take care not to drop tapes or cassettes. Do
not touch the surface or the edge of the tape.
of the tape by dirt, dust, food, cigarette smoke, and airborne
pollutants. Cleanliness is important because minute debris can cause
loss of signal or dropouts. The frequent appearance of dropouts is
an indication that the videotape playback device is contaminated
with dirt and/or that the tape is deteriorating.
especially modern ones, are recorded with high levels of magnetic
energy that make them relatively immune to problems from common
household magnetic fields. Weak magnetic fields are produced around
electrical appliances, power tools, and television sets. However it
is good practice to avoid exposing tapes to any magnetic fields. A
few feet separation from a magnetic source will usually provide
sufficient protection. Airport walk-through metal detectors and
x-ray machines are probably safe, but hand inspection by airport
security personnel will ensure an extra level of protection.
When tapes are not
in use, store them on end (like books on a library shelf) to prevent
deformation. Do not store videotapes lying flat. When housed in a
horizontal position, pressure from other tapes can cause
distortions. Rewind tapes after recording or playback.
A tape must not be
left threaded in the video recorder for a long period. Leaving a
tape in the playback machinery overnight, for example, is not
desirable. Likewise, tapes should be inserted and ejected only at
blank, unrecorded sections. Never eject a tape in the middle of a
recording. Pausing tapes for prolonged periods also results in
degraded image quality. After recording, rewind the tape before
Always return tapes
to carefully labelled protective inert plastic containers when they
are not in use. Cardboard boxes deteriorate over time and provide
little protection from handling, environmental fluctuations, fire,
must be cared for and cleaned regularly following recommended
maintenance procedures. Protect VCRs with a dust cover. Dirt in the
tape path through the machine can permanently scratch the
Always use a new,
brand-name tape from a recognized manufacturer for important
recordings. Avoid extended-play tapes because they use a thinner
polyester tape base and, therefore, are less wear resistant. Before
recording it is good practice to wind the tape from one hub to
another and then back. This procedure will relieve stresses on the
tape that could result in a slightly irregular passage of the tape
through the recorder. Record at standard speed. Always break off the
tab on a videocassette to prevent accidental re-record. Make
protection copies of the most valuable videotapes and keep them in a
strikes, it can leave a single tape or an entire collection
unusable. For this reason, videotapes must be well protected from
damage by fire or water. Magnetic tape cannot tolerate high
temperatures. Temperatures above 150 degrees F can cause permanent
damage to videotape. In the unfortunate event of a disaster,
experience, research, and testing have led to the development of
highly effective restoration and remastering techniques that may
preserve lost or damaged information.
may require duplication onto a new tape stock (called reformatting).
This is especially true if the original recording was done on a type
of machine that is no longer in production (like Sony Betamax).
Tapes that are ten years old or older or that have been poorly
stored and improperly handled are a high priority for restoration.
Restoration is the process by which a videotape, degraded by age, is
temporarily or permanently transcribed to a playable condition. The
restoration process usually requires highly technical methods and
conservators are skilled in many of the preventive preservation
techniques that can prolong the life of your videotape. Conservators
will also provide information on restoration and conservation
services that may be required for videotapes that are severely
damaged or obsolete.
Further Reading and
Video Preservation: Securing the Future of the Past. New York: Media
Alliance, 1993 (Media Alliance, c/o Thirteen/WNET, 356 W. 58th St.,
New York, NY 10019)
Van Bogart, John.
Magnetic Tape Storage and Handling: A Guide for Libraries and
Archives. Washington, DC: National Media Lab and Commission on
Preservation and Access, 1995. (Commission on Preservation and
Access, 1755 Mass. Ave., NW, Ste. 500, Washington, DC 20036;
Moving Image Archivists
c/o National Center for Film and Video Preservation
P.O. Box 27999
2021 N. Western Ave.
Los Angeles, CA 90027
National Media Lab
P.O. Box 33015
St. Paul, MN 55133 - 3015
and Records Administration
Motion Picture Sound and Video Branch
8601 Adelphi Rd.
College Park, MD 20740 - 6001
Library of Congress
Motion Picture Broadcasting and
Recorded Sound Division
Washington, DC 20540-4500
This information is
provided courtesy of the American Institute for Conservation of
Historic and Artistic Works (AIC), the national membership
organization of conservation professionals dedicated to preserving
the art and historic artifacts of our cultural heritage for future
generations. Among other services of the AIC is the Guide to
Conservation Services, which provides a free list of conservators in
your geographic region. The AIC brochure Guidelines for Selecting a
Conservator, will help you make an informed choice.
in this brochure are intended as guidance only, and AIC does not
assume responsibility or liability.
Prepared by Debbie
Hess Norris with assistance from Peter Adelstein, Deirdre Boyle,
Connie Brooks, Alan Lewis, Jim Lindner and Paul Messier, 1997