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RE: arsclist VHS and S-VHS Tapes
Dear Mary (I hope I may call you that),
Thankyou for describing your problem. Although I'm not a video engineer,
I've been fighting the things for nearly thirty years now, and this is my
view.
The mini-DV format is the worst of all digital video formats, because it
is utterly dependent on loving care-and-attention to get so much information
into such a small space. Without consulting me, one of our curators sent a
team of two to India, who had volunteered to document some of the visual
aspects of traditional Indian music (costumes, decor, the manufacture of
body paint, etc.) The first two DV cassettes came back, and *then* I was
asked how to preserve them!
I sent them to one of our audio contractors who also does work for the
BBC, and he advised me (a) to make a digital clone onto a format called
DVCAM (I'm afraid I know nothing about this, but apparently it's the only
way you can move DV-compressed data onto another medium without
decompression and recompression losses. DVCAM isn't widely used, but it
takes about half as much space again as the DV data, so various geometrical
problems have less effect); and (b) make *two* timecoded copies on VHS
(DVCAM will also hold timecode not-in-picture), so users may see the
contents and know what scenes to call up from the DVCAM version without any
further losses occuring. And the original DV might still be playable if all
this fails!
From the point of view of audio (which is what I'm employed to know),
both DV and DVCAM both use 16-bit 48kHz, so the audio can be preserved in
many ways (but not, unfortunately, on CD-R).
Whilst S-VHS equipment is still available here (we are traditionally a
couple of years behind the Americans in things like this), I would
reluctantly agree its time is up. The problem is that there does not seem to
be an archivally valid substitute, either analogue or digital. So I propose
to spend some of my savings to keep my personal S-VHS system running,
knowing there is a backup at the NSA, and knowing the weaknesses of VHS very
well!
Sorry this is a rather negative answer to your question, as well as a
financially difficult one; but thank goodness DV has a reasonable soundtrack
(if nothing else).
Peter Copeland
<peter.copeland@xxxxx>
-----Original Message-----
From: Mary Habstritt [mailto:nystudio@xxxxxxx]
Sent: 28 February 2002 21:45
To: ARSCLIST@xxxxxxxxxxxxxxxx
Subject: Re: arsclist VHS and S-VHS Tapes
Hello,
I joined this list and the AMIA list some time ago when realizing I needed
to learn a lot to preserve the audio- and videotape collection that came
with this job.
This archives contains lectures by artists and art critics going back to
1964 and the lecture series is ongoing.
It was recommended to me that we should be making our new originals on S-VHS
tape. Our VHS camera broke some time ago (before my time) and we have been
making originals on mini-DV for about a year.
I found new S-VHS equipment hard to find. B&H only carries one model of
S-VHS camera and, due to fiscal crisis this summer, was out of our price
range.
I thought I'd make S-VHS copies of the mini-DV originals on hand so far, but
it sounds like this is not really useful since the digital original does not
have the carrier strength. Correct?
The lab I use for making tape copies charges more than twice the usual cost
for S-VHS ($50) as opposed to VHS ($20) and tells me S-VHS is a format on
its way out. Any comments on that?
(P.S. I only have copies made on demand as I want to save the money for
equipment! I have no equipment for playing or copying the mini-DVs--just
that darn camera.)
Mary Habstritt
library@xxxxxxxx
John McEnroe Library
New York Studio School
8 West 8th Street
New York NY 10011
212-673-6466, ext. 18
----- Original Message -----
From: "Copeland, Peter" <Peter.Copeland@xxxxx>
To: <ARSCLIST@xxxxxxxxxxxxxxxx>
Sent: Thursday, February 28, 2002 4:34 AM
Subject: RE: arsclist VHS and S-VHS Tapes
> Dear All,
> This discussion is becoming somewhat prolonged, largely my fault I'm
> afraid.
> Mike Richter raised the very real point that the audio Hi-Fi tracks
use
> reciprocal noise reduction. (I insert that word "reciprocal", because when
> everything works well, you get back the original undistorted sound, as
> opposed to other noise-reduction processes which *aren't* reciprocal, such
> as the second and third stages of "The Packburn", or the Philips DNL ( =
> Dynamic Noise Limiter)). When the carrier-levels of the hi-fi tracks
aren't
> very strong, the dBx-type expander can emit added noise from the
> head-switching circuitry (or from a poor playback head, or one slightly
> off-track), which it cannot hide. This is because the video is recorded
> using analogue FM (frequency modulation) principles, like a local radio
> station. Conventional hocus-pocus suggests that FM radio is only
noise-free
> so long as the carrier-level is about double any interfering noise. That
is
> the main argument in favour of using S-VHS tape for preservation purposes;
> when something isn't right, you've got about double the carrier strength
to
> play with.
> A second consideration (as you may guess from the last paragraph of my
> original posting) is that we're often handling music broadcasts. The
> dBx-type noise-reduction is always upset in the presence of unwanted
sounds
> outside the audio frequency-range. In Europe, broadcasters generally (but
> not always) bandwidth-limit their transmissions to prevent such
> side-effects. As an anecdote to explain my meaning more clearly, the worst
> hi-fi track I have had to deal with was of a Wagner opera from the Royal
> Opera House here in London. Normally, Wagner's music will drown anything;
> but there was a moment where a solo soprano was singing softly and without
> orchestral accompaniment, lamenting the death of her lover. The
combination
> of the out-of-band noise from the Royal Opera House's air-conditioning,
the
> quietness of the wanted sound (very close to the head-switching noise on
the
> hi-fi track), and the vibrato, meant it was very difficult to get the
sound
> clear of the noise. It's some years ago now; but I believe we had to buy a
> new machine with new heads and perfect mechanical alignment to cover the
> noise!
> But, had it been on S-VHS tape, there wouldn't have been a problem.
> With regard to Brian Levy's note below, I would only back up CD-Rs
using
> digital methods, and I would only use VHS or S-VHS if you have enough Sony
> PCM-F1 processors (or equivalents) to get you through the next fifty years
> or so. I believe *we* have. You would also need something called a PCM-601
> to convert from SP-DIF into the digitised-audio video domain. We've only
got
> one; if anyone would like to sell me another, I'm open to offers!
> Peter Copeland
>
> -----Original Message-----
> From: Brian Levy [mailto:xernaut@xxxxxxxxx]
> Sent: 28 February 2002 06:40
> To: ARSCLIST@xxxxxxxxxxxxxxxx
> Subject: Re: arsclist VHS and S-VHS Tapes
>
>
> Dear Peter,
>
> What about the possibility, as suggested to me by someone working at one
of
> the places I purchase blank CD-R media for our Indian language
> preservation projects here in Oklahoma, of using S-VHS to store analog
> back-ups to all our CD-R's in our archive, just in case the digital
> strategy fails? Since quarter inch reel is expensive, especially for a
> smaller archive with little funding, like ours, might'nt this be a smart
> choice?
> Thanks for your posting,
> Brian Levy
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