9. Minimizing signal loss.
There is no way to prevent signal loss or
degradation when transferring from one tape to another. However, there are
some ways to minimize signal loss.
a. Use a first generation tape (hot edit) whenever possible.
b. Use a time base corrector (TBC).
c. Use a high density tape; using old or worn-out tape adds noise to
the video signal.
d. When editing or dubbing, always try to edit down. That is, edit or
dub from 2-inch tape to 1-inch tape to 3/4-inch tape to 1/2-inch tape (fig
1-7).
Figure 1-7.
1-inch VTR and 3/4-inch VCR
10. Control track.
Basically, a control track (referred to as electronic
sprocket holes), is an electronic signal laid on the outer edge of the video
tape. The control track consists of 30 electronic sync pulses recorded each
second. The most critical element of the control track is the requirement
that all of the pulses be recorded at the same distance or time apart. When
the tape is played back, the play-back VTR reads these pulses and uses them
to control the speed of the rotating video heads; therefore controlling the
relationship between the head speed and tape speed. Without a good control
track, it is not possible to edit in the INSERT mode and it is almost
impossible to get a stable picture.
a. Since the control track is recorded along the outer edge of the
video tape, it is important that the outer edge of the tape remains free
from damage by tearing, wrinkling, or creasing.
Should the control track
become damaged, you must replace the
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