On Fri, Dec 31, 2004 at 09:29:41AM -0800, Steven Boswell II wrote:
> >Aieee - but if you're using a composite cable then the VCR is
> >MASHING/MUSHING/CURDLING/DOWNGRADING/etc the Y and C signals into
> >a composite signal - that is a LOSSY (and damaging) conversion and
> >even the best Y/C separator can not recover the original signals
> >100% accurately.
>
> Eh? I thought VHS videotapes were composite video, and that
> composite video means the intensity/color/sync were all mixed
> together in the same signal. Am I wrong?
Both VHS and Beta physically store the video signals on the tapes as
separate color and luma information (among other things, the signal
on the tape is frequency division multiplexed). So in theory, if the
vcr has S-vid outputs, the only conversion that needs to happen is
converting from the tape storage format to the S-vid signal format.
No combining of color/luma onto the same signal (composite) need
occur. This of course assumes that is how the VCR is designed.
Steven's comment about checking the schematics is valid, without
that, it's all just guesswork.
The other's in this thread all have points. If you recorded from
broadcast TV signals, then the signal was already "damaged" by being
combined, so there is not likely much left to lose either way.
But, depending on the quality of the composite video generation
circuits in your vcr (and assuming it's designed this way), using the
S-vid connection very well may just prevent yet further signal loss
or noise addition.
Compare:
/------ luma -- tape ------------->---
composite --- S-vid cable
\------ color -- tape ------------->---
With:
/------ luma -- tape ---\
composite --- --------->--- composite cable
\------ color -- tape ---/
The recombine step could introduce additional loss/noise into the
composite signal that wouldn't be present in the S-vid signal. The
conversion to/from tape storage format has to occur no matter what,
so there's no way to avoid that step.
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