I was watching a never-previously-broadcast *colour* version of Last
Night at the Sunday Palladium (shown a year so ago on Talking Pictures
TV), made as an experiment before PAL broadcasts began. As far as I
could tell, it had not been film-recorded.
That led me to think... if it had been originally recorded on 2" Quad
tape, would that tape still be playable today (assuming it had been
stored in ideal conditions)? I imagine at some stage it was converted
from analogue video to a modern digital video format for broadcast by
TPTV, but would Quad VT last long enough to do that during the time
that digital formats have been used, or would it have been copied to
another more recent analogue format (one of the 1" or 3/4" formats)
some time in the past before the Quad tape deteriorated?
In message <uma38a$2mnhj$2@dont-email.me> at Sun, 24 Dec 2023 20:10:32, NY <me@privacy.invalid> writes
I was watching a never-previously-broadcast *colour* version of Last Night >>at the Sunday Palladium (shown a year so ago on Talking Pictures TV), made >>as an experiment before PAL broadcasts began. As far as I could tell, it >>had not been film-recorded.
Did you get the impression that it _had_ been PAL, just before actual broadcasting began, or one of the several other schemes the Beeb tried
out? (I presume not 405, or you'd have mentioned it. I know they did do
some 405 colour trials, including a special version of NTSC!)
I was watching a never-previously-broadcast *colour* version of Last Night at the Sunday Palladium
"NY" <me@privacy.invalid> Wrote in message:
I was watching a never-previously-broadcast *colour* version of Last
Night at the Sunday Palladium
Was that a real show, a Mollyprop/Spooner joke, or just a typo on
your part?
I've only heard of "Sunday Night at the London Palladium"
Good wonder. I suspect you're right that it went via something else.
Probably hard to tell unless someone knows a format-specific artefact to
look for: if done with professional kit, I expect a generation or two of extra copying would not degrade it enough to tell.
On 25/12/2023 01:21, J. P. Gilliver wrote:
Good wonder. I suspect you're right that it went via something else.
Probably hard to tell unless someone knows a format-specific artefact to
look for: if done with professional kit, I expect a generation or two of
extra copying would not degrade it enough to tell.
It's often possible to recognise Quad; sometimes you can see a glitch
every 15 lines, either a slight hiccup in the sync or change in colour.
In message <D9mdnb-muu4-hw34nZ2dnZfqn_adnZ2d@brightview.co.uk> at Sat, 30
Dec 2023 13:27:01, Laurence Taylor <laurence@nospam.plus.com> writes
On 25/12/2023 01:21, J. P. Gilliver wrote:What I meant was - yes, those who know might well be able to tell what it
Good wonder. I suspect you're right that it went via something else.
Probably hard to tell unless someone knows a format-specific artefact to >>> look for: if done with professional kit, I expect a generation or two of >>> extra copying would not degrade it enough to tell.
It's often possible to recognise Quad; sometimes you can see a glitch
every 15 lines, either a slight hiccup in the sync or change in colour.
was _originally_ on, but - if done with good-quality gear by someone who knows what they're doing - it probably _isn't_ possible to tell whether
what you're seeing is direct from the Quad (or whatever), or has been
stored on something else (1" or whatever) for most of the intervening
time.
"J. P. Gilliver" <G6JPG@255soft.uk> wrote in message >news:1pU81bzPQCklFwqj@255soft.uk...
In message <D9mdnb-muu4-hw34nZ2dnZfqn_adnZ2d@brightview.co.uk> at
Sat, 30 Dec 2023 13:27:01, Laurence Taylor <laurence@nospam.plus.com> >>writes
On 25/12/2023 01:21, J. P. Gilliver wrote:What I meant was - yes, those who know might well be able to tell
Good wonder. I suspect you're right that it went via something else.
Probably hard to tell unless someone knows a format-specific artefact to >>>> look for: if done with professional kit, I expect a generation or two of >>>> extra copying would not degrade it enough to tell.
It's often possible to recognise Quad; sometimes you can see a glitch >>>every 15 lines, either a slight hiccup in the sync or change in colour.
what it was _originally_ on, but - if done with good-quality gear by >>someone who knows what they're doing - it probably _isn't_ possible
to tell whether what you're seeing is direct from the Quad (or
whatever), or has been stored on something else (1" or whatever) for
most of the intervening time.
I presume that every recording technology imprints its own "footprint"
on the signal because of restrictions of the format. The Quad banding
is an extreme example of this. Whether those footprints are visible to
the viewer, or in most cases is only detectable with an oscilloscope or >vectorscope, is another matter.
I wonder if any archive material still exists as videotape nowadays, or >whether archives have digitised everything so (barring catastrophic >corruption of DAT or HDD masters) the recording does not deteriorate
any further over time.
I have been surprised when TV news reports are included in
documentaries about historical events (even as recent as the 1980s),
how poor the picture quality is sometimes - as if the only copy in
existence is a 2nd generation VHS ;-) Of course in some cases
documentary makers deliberately degrade the quality with ageing
effects, to say to the viewer "this is archive, not a modern
recording". And so you get monstrosities such as film scratches and
dirt on an ENG (and therefore video camera and videotape) report.
Sometimes the effects are even more crass - I remember a programme
about the Iranian Embassy siege in the 80s, and the often-seen footage >"filmed" with video cameras had been fed through an effects box which
added film scratches, film gamma changes, fake film grain and venetian >blinds. A caption "archive" would have been so much less intrusive.
What is the typical life of videotape as a means of long-term storage,
before the oxide starts to shed or the tape base starts to become
brittle?
In message <un0m4v$2k453$1@dont-email.me> at Tue, 2 Jan 2024 09:46:33,
NY <me@privacy.invalid> writes
"J. P. Gilliver" <G6JPG@255soft.uk> wrote in message >news:1pU81bzPQCklFwqj@255soft.uk...
In message <D9mdnb-muu4-hw34nZ2dnZfqn_adnZ2d@brightview.co.uk> at
Sat, 30 Dec 2023 13:27:01, Laurence Taylor <laurence@nospam.plus.com> >>writes
On 25/12/2023 01:21, J. P. Gilliver wrote:What I meant was - yes, those who know might well be able to tell
Good wonder. I suspect you're right that it went via something else. >>>> Probably hard to tell unless someone knows a format-specific artefact to >>>> look for: if done with professional kit, I expect a generation or two of >>>> extra copying would not degrade it enough to tell.
It's often possible to recognise Quad; sometimes you can see a glitch >>>every 15 lines, either a slight hiccup in the sync or change in colour. >>>
what it was _originally_ on, but - if done with good-quality gear by >>someone who knows what they're doing - it probably _isn't_ possible
to tell whether what you're seeing is direct from the Quad (or >>whatever), or has been stored on something else (1" or whatever) for >>most of the intervening time.
I presume that every recording technology imprints its own "footprint"
on the signal because of restrictions of the format. The Quad banding
is an extreme example of this. Whether those footprints are visible to
the viewer, or in most cases is only detectable with an oscilloscope or >vectorscope, is another matter.
Indeed. The quad banding is indeed visible to those who know what to
look for. (Another visible effect - though not due to the recording
format - was visible on reports from the Falklands, when equipment
presumably not designed for such field strengths was used in close
proximity to ship's radar; it occurred to me at the time that this might
be giving away information about the pulse characteristics thereof which would be of use to the enemy [it clearly wasn't just a plain beam], but nothing such has ever been revealed.)
I wonder if any archive material still exists as videotape nowadays, or >whether archives have digitised everything so (barring catastrophic >corruption of DAT or HDD masters) the recording does not deteriorate
any further over time.
One would hope so, but it's an expensive business, so probably not. Plus
the oft-raised point that - for some archives, anyway - the hours of
archive material they hold exceed the remaining use hours of the
machines they have still working, so they're kept for when it's actually required for something rather than continuous background conversion.
In article <UyKBGnFHRAllFwn$@255soft.uk>,[]
J. P. Gilliver <G6JPG@255soft.uk> wrote:
In message <un0m4v$2k453$1@dont-email.me> at Tue, 2 Jan 2024 09:46:33,
NY <me@privacy.invalid> writes
I wonder if any archive material still exists as videotape nowadays, or
whether archives have digitised everything so (barring catastrophic
corruption of DAT or HDD masters) the recording does not deteriorate
any further over time.
One would hope so, but it's an expensive business, so probably not. Plus
the oft-raised point that - for some archives, anyway - the hours of
archive material they hold exceed the remaining use hours of the
machines they have still working, so they're kept for when it's actually
required for something rather than continuous background conversion.
I remember being involved in Standards Converting 405 material to 625 for >archive purposes.
I wasn't thinking so much of the electronics, as the heads. The skills
to repair the electronics - though I suspect increasingly rare -
probably are still findable (and the circuitry of the machines is
probably at least moderately well documented), but that to make the
heads - and the machines and materials required to do so - will be much rarer. Perhaps other mechanical parts too.
Beta might have been the choice, but it was my understanding that they created standard video signals (and reasonably low bandwidth at that),
so presumably they could have been recorded on VHS or V2000 too.
IIRR, it's also why we have the rather odd sampling rate of 44100 hertz
- it sort of fell out of the pseudo-video waveform creation, and the
SECAM and "PAL" (yes I know) standards.
Will we see a raiding-of-attics-and-sheds like we did for old Doctor Who
(and other) video recordings, this time for machines (even ones that
don't work, provided the heads are OK)!
On 02/01/2024 14:45, J. P. Gilliver wrote:
I wasn't thinking so much of the electronics, as the heads. The skills
to repair the electronics - though I suspect increasingly rare -
probably are still findable (and the circuitry of the machines is
probably at least moderately well documented), but that to make the
heads - and the machines and materials required to do so - will be much
rarer. Perhaps other mechanical parts too.
The heads are the only real problem. Everything else can be made using
a lathe and a milling machine if you have an old one as a pattern or
the drawings. Making heads is a different kettle of fish.
In the early days of digital audio, Betamax video recorders were used
to carry the digital signal on tape. The amount of tape which exists
and which people would like to archive now exceeds the expected life of
all the Betamax heads currently in existence, and it would be too hard
or expensive to rebuild the head making machinery.
On 02/01/2024 18:30, J. P. Gilliver wrote:
Beta might have been the choice, but it was my understanding that theyBetamax had a sightly better HF response than other systems at the
created standard video signals (and reasonably low bandwidth at that),
so presumably they could have been recorded on VHS or V2000 too.
time, due to a higher speed of the heads across the tape, so the tapes
were easier to decode accurately. Betamax recorders were also better
built than almost all VHS recorders of the period. V2000 was later,and
also had a problem in that the cassette could hold two programmes,
depending on which way up it was, because it only used half the tape
width at a time. It never really caught on, especially as the two major >manufacturers initially made recorders which were not completely
compatible with each other's tapes.
IIRR, it's also why we have the rather odd sampling rate of 44100 hertzIt let them use the same crystals for sample timing as for the PAL
- it sort of fell out of the pseudo-video waveform creation, and the
SECAM and "PAL" (yes I know) standards.
colour sub carrier, if I remember correctly. Meant they cost pennies
instead of pounds when the first CD players came out.
Will we see a raiding-of-attics-and-sheds like we did for old Doctor Who
(and other) video recordings, this time for machines (even ones that
don't work, provided the heads are OK)!
Possibly, they are already searching repair shop storerooms for new old
stock heads that never got used to repair machines.
In message <kvj53iFd847U1@mid.individual.net> at Tue, 2 Jan 2024
19:05:21, John Williamson <johnwilliamson@btinternet.com> writes
built than almost all VHS recorders of the period. V2000 was later,and
also had a problem in that the cassette could hold two programmes,
depending on which way up it was, because it only used half the tape
I don't see that as a problem - advantage, if anything!
V2000 was later,and also
had a problem in that the cassette could hold two programmes, depending
on which way up it was, because it only used half the tape width at a
time.
In message <kvj53iFd847U1@mid.individual.net> at Tue, 2 Jan 2024
19:05:21, John Williamson <johnwilliamson@btinternet.com> writes
It let them use the same crystals for sample timing as for the PAL
colour sub carrier, if I remember correctly. Meant they cost pennies
instead of pounds when the first CD players came out.
Oh, I thought it was because of the two different video standards
(625/25 and 525/30) and the need to find a rate that could be converted
to both of those.
On 02/01/2024 19:29, J. P. Gilliver wrote:
In message <kvj53iFd847U1@mid.individual.net> at Tue, 2 Jan 2024
19:05:21, John Williamson <johnwilliamson@btinternet.com> writes
It let them use the same crystals for sample timing as for the PAL
colour sub carrier, if I remember correctly. Meant they cost pennies
instead of pounds when the first CD players came out.
Oh, I thought it was because of the two different video standards
(625/25 and 525/30) and the need to find a rate that could be converted
to both of those.
Yes I thought it was a frequency that was usable on both TV systems.
I hadn't realised that recording sound digitally on videotape pre-dated
the CD standard and therefore determined the CD sampling rate. I'd
always thought that sound-on-videotape came after CDs.
On 02/01/2024 19:05, John Williamson wrote:
V2000 was later,and also had a problem in that the cassette could
hold two programmes, depending on which way up it was, because it
only used half the tape width at a time.
I never knew that any of the VCR formats allowed the tape to be turned
over and only used half the track. I've learned something.
I remember turning the tape upside down in a VHS cassette that had a
badly mangled tape in one part and so could never be used in it
entirety and was too much of a risk of the bad bit being
played/recorded on by accident, clogging the heads. So I had a play. I
wound the tape all onto one spool, cut the tape and reattached the
empty takeup spool upside down, then wound the tape completely onto
that, and then turned the now-empty spool upside down. With the reels
the correct way up in the cassette, the tape was now upside down.
And it played! Very noisy picture, monochrome only, motion in reverse, >picture upside down. I was gobsmacked that it worked at all. I suppose
the line-sync pulses now applied to the previous line (the end of one
line becomes the beginning of a neighbouring one.
On 02/01/2024 19:29, J. P. Gilliver wrote:
In message <kvj53iFd847U1@mid.individual.net> at Tue, 2 Jan 2024
19:05:21, John Williamson <johnwilliamson@btinternet.com> writes
It let them use the same crystals for sample timing as for the PAL >>>colour sub carrier, if I remember correctly. Meant they cost pennies >>>instead of pounds when the first CD players came out.Oh, I thought it was because of the two different video standards
(625/25 and 525/30) and the need to find a rate that could be
converted to both of those.
Yes I thought it was a frequency that was usable on both TV systems.
I hadn't realised that recording sound digitally on videotape pre-dated
the CD standard and therefore determined the CD sampling rate. I'd
always thought that sound-on-videotape came after CDs.
I was watching a never-previously-broadcast *colour* version of Last Night
at the Sunday Palladium (shown a year so ago on Talking Pictures TV), made
as an experiment before PAL broadcasts began. As far as I could tell, it had not been film-recorded.
That led me to think... if it had been originally recorded on 2" Quad tape, would that tape still be playable today (assuming it had been stored in
ideal conditions)? I imagine at some stage it was converted from analogue video to a modern digital video format for broadcast by TPTV, but would Quad VT last long enough to do that during the time that digital formats have
been used, or would it have been copied to another more recent analogue format (one of the 1" or 3/4" formats) some time in the past before the Quad tape deteriorated?
On 05/01/2024 17:01, Bill Posters wrote:
The length of early CD's appears to be dictated by the longest U-Matic
available, which was 74 minutes and made by BASF
I thought that apocryphally it was based on a requirement by someone who influenced the spec, that the whole of a certain orchestral symphony had
to fit on one disc.
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