X-Laurel_VP
Imported Account
Jan 30, 2000, 1:22 PM
Post #3 of 3
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Re: ntsc monitor jiggles like jello
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There may be two problems here -
1) If the computer and television monitors are too close to
one another and are inadequately shielded, the magnetic field
created by one monitor may affect the other, causing a wavering
or rippling effect. This is because the two monitors are
running at different vertical refresh rates (color video at
59.95 Hertz and computer video running at anything from
50 to 85 Hertz). Horizontal scan frequencies can differ,
too, creating cross-monitor interference.
Solution: Try separating the monitors.
2) Within the television signal there are horizontal and
vertical synchronizing signals ('sync pulses', etc.).
Television monitors and VCR's need these signals to time
themselves and display or record/playback stable images.
When you pause certain VCR's (especially those without
built-in time base correctors), the sync signals are not
always output. The monitor tries its best to produce a
viewable image, but it may be distorted. I suspect some
video capture/playback cards may also not output sync
signals when not in preview/playback mode.
I believe that there is no standard sync information in the
DV datastream (as there is in analog video) coming through
your 'firewire', so it's up to the computer's capture card
to create sync info to send to its composite/s-video output.
When your GV-D300 is in pause, the capture board doesn't
know what to do, video sync-wise, therefore causing that
'wavering' in your monitor's display.
The text display of your VCR's menu screen is keyed (super-
imposed) over video - either tape playback or a plain screen
if in stop mode. If no video is present (stop mode with no
video signal connected to the VCR input) or the VCR is in
pause mode (with no accurate sync signal), the text will
jiggle because the VCR's built-in character generator
(that creates the menu screen) cannot sync to proper video.
-S.T.
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