VCR Tapes
Understanding the Problem
VCR tape is created when metal oxides, lubricants, and plasticizers are "bound" to a "base" of clear polyester tape. This mix of chemicals serves a variety of purposes. Metal oxide records the magnetic impulses that are "read" by the VCR to recreate images on a television screen. Plasticizers help keep the film supple so it is less likely to break or stretch. Lubricants serve a similar purpose by helping to keep the tape moving smoothly through the mechanical transport system that moves the film from one spool, past the VCR "head," the device that "reads" the magnetic pulses recorded on the metal oxide, and on to the other spool.Each of the component parts of the finished tape is subject to unique problems and a failure of any one of them can make the tape unplayable. Because the mix of component parts is complex even the best quality tape can begin to degrade quite quickly, often within a year or two after its manufacturing. Even under ideal conditions the binder that holds together this mix of chemicals is very delicate and it is usually quite easy to scrape off parts of the chemicals from the base. For whatever reason as degradation occurs the image that is played back on a television screen becomes poorer and poorer, until it can no longer be viewed.
The Enemies of VCR Tape
VCR tape is subject to harm from a variety of sources. Just as with paper and photographs heat can speed the chemical reactions that cause the tape to fail and humidity can encourage the growth of various biological agents that can destroy the tape."Binder breakdown" is a frequent cause for tape failure. Like all adhesive agents, as the binder ages it begins to lose its "stick." As this happens microscopic pieces of oxide as well as the other chemicals imbedded in the binder slowly fall away. As each bit of oxide is lost, a small piece of information is lost creating various problems when the tape is played.
Because VCR tape can only be viewed by playing it through a complicated mechanical device, a VCR, it is also frequently damaged by mechanical problems within a VCR. Dirt is the most frequent problem. Dirt, even microscopic particles, if located in strategic spots on the transport mechanism or VCR head can cause continual scratching of the VCR tapes. Each scratch scrapes off a bit more material from the polyester tape base and each loss of material further degrades the image.
Preserving VCR Tape
There is no long-term strategy for preserving VCR tape. It is reasonable to expect that most VCR tape, for one reason or another, will be unplayable after approximately a decade. Within this short life-span, however, it is possible to take steps that will keep the tape and the images preserved on the tape, in better condition, thus allowing for a higher quality copy of the tape to eventually be made.Practical suggestions for maintaining VCR tape in good condition include:
Buy name brand VCR tape. The chemicals used by various manufacturers, quality control practices, and other procedures vary dramatically between manufacturers, with "no-name" tape usually being made as cheaply as possible. Lacking good studies on the reliability of various brands of VCR tape, a consumer can at least fall back on the advice that you often get what you pay for, and buying the cheapest tape available is asking for preservation trouble.
Make a "preservation" copy of the VCR tape as soon as it is shot. This can be done at home by mating two VCRs or it can be done at many shops which do VCR repairs. Check the preservation copy once a year, but otherwise never play it. This "pristine" copy will serve you well when the time comes to copy the tape onto a new tape. Pull out a second, "user" copy of the tape to show friends, neighbors, and relatives. Although with each viewing the user copy will slowly degrade, the images will be preserved in the best possible state on the "preservation" copy.
VCR tape should be viewed and rewound annually. Annual viewing makes it possible to detect problems before they lead to the catastrophic failure of the tape. Annual rewinding helps avoid a number of problems that can occur as the tightly wound VCR tape rests up against itself.
Always use a clean, well-functioning VCR machine to play the tape. Microscopic particles of dirt can cause irreparable damage to the tape as it races past the VCR head. Professional cleaning of a VCR machine, including demagnetization of the head, is always a good idea before the family tapes are pulled out for their annual screening. It is particularly important to make sure the VCR has recently been serviced before playing the preservation copy of your tapes.
Assume VCR tape will have to be copied. The medium of tape is very fragile and subject to a variety of fatal harms. Plan on copying tape at least once every ten years.
VCR Tape: A Checklist
- Buy name brand tape.
- Make a "preservation" copy of family tapes that will be used for subsequent copying.
- View and rewind VCR tape annually in order to find image degradation before significant tape failure occurs.
- Play family tapes (particularly a preservation copy) through a recently cleaned and adjusted VCR machine.
- Assume VCR tape is a temporary medium and plan on regularly copying the tape.
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