NTSC versus PAL
William Sommerwerck
As both PAL and NTSC are basically dead systems (NTSC in the US, at least),
there is little point in discussing their differences. But as Mr. Alison
insists on displaying his ignorance in public, I'm going to, anyhow.
The first color TV system approved by the FCC was a field-sequential (or
frame-sequential -- I forget which) system proposed by CBS. It was developed
by Peter Goldmark, the same man given credit for the modern LP phonograph
record. (I say "given credit for", because there have been questions as to
whether he was the principal designer.)
The CBS system is a classic example of a design botched from the get-go. At
that time (not long after WWII), there was no practical way to display three
color images simultaneously with a single CRT. So Goldmark went with a
spinning color wheel, a system that had been tried 25 years earlier for
color motion pictures, and found wanting.
The problems with such a system are obvious, but I'll describe them. One
problem is that it requires three times as much film (or in the case of TV,
three times the bandwidth). Another is that moving objects show color
fringing.
Then there was the problem of the spinning color-filter disk. A 10" TV would
require one at least 2' in diameter. Imagine the disk needed for a 21" set!
(Not to mention the noise, and the possibility, however remote, of
decapitating the cat.)
These obvious (and lethal) deficiencies didn't deter Goldmark or CBS,
because they were in competition with RCA/NBC. The CBS argument was... Why
limit TV to B&W? Why not /start/ with a color system, and be done with it?
CBS pressed the FCC (as one writer pointed out, every sale of an RCA B&W TV
would be another nail in the coffin of the CBS color system), and in 1950
the CBS system was approved, despite the fact it was wholly incompatible
with the 480i system already in use. *
David Sarnoff ("the most-nasty name in electronics") was naturally upset.
RCA had to make CBS look bad, while completing development of their own
color system. Sarnoff gleefully pointed out that the CBS system was
"mechanical", and subject to all the limitations accruing thereto. Though
this was literally true, it overlooked the fact that one can have
all-electronic field-sequential color. But -- on the other hand -- CBS had
nothing other than a mechanical system to offer.
RCA was working on a "dot-sequential" system. Each line of the image was
divided into 300 (or so) pixels **, with red, green, and blue samples
alternating. This system worked fairly well -- it produced an acceptable
picture on B&W sets. But (for reasons I don't remember) color receivers had
problems displaying B&W images. As color receivers would (initially) be used
mostly for B&W viewing, this was not acceptable
The breakthrough came when engineers at Hazeltine and GE remembered Monseuir
Fourier, and recognized that sampling the colors was equivalent to a
"continuous" signal at the sampling frequency. They "slipped a note under
RCA's door" (so to speak), and NTSC/PAL came into existance. The color
information was transmitted on a subcarrier whose sidebands were interleaved
with the luminance sidebands, to minimize interaction. ***
"...complete with bad commercials that repeat all night, both in compatible
color and black and white." -- Stan Freberg
The brilliance of NTSC/PAL is that their signals produce as good (or better)
an image on B&W sets, and display excellent color on a color set -- without
making any existing equipment obsolete, and without requiring additional
bandwidth.
So... why is NTSC "better" than PAL? For one thing, it has "better" and
"more" color. Although the original NTSC proposal used red and blue color
signals of equal bandwidth, it was recognized that this didn't fit with the
way the eye actually sees color.
It turns out that for a 480-line system displayed on a 21" tube, the eye
sees full color (red/green/blue) only to about 0.5MHz. From 0.5MHz to
1.5MHz, the eye sees only those colors that can be matched with red-orange
and blue-green primaries. **** The system was therefore changed to the
red-orange/blue-green and yellow-purple primaries, the former of 1.5MHz
bandwidth, the latter of 0.5MHz bandwidth.
PAL uses equal-bandwidth (1.0 MHz) red and blue primaries. If an NTSC set
fully demodulates the 1.5MHz color signal (most limit it to 0.5MHz to make
the set cheaper), more of the original image's color detail will be
displayed (though this will be visible mostly in graphics).
Much has been made of PAL's phase alternation, especially its supposed
ability to eliminate the need for a tint [sic] control. (It should be hue
control.) When was the last time you adjusted the hue control on an NTSC
receiver? 30 years ago?
This issue is confused by two factors -- the differences between European
and American distribution systems, and their studio standards.
If the transmission network has constant group delay, the hue setting should
be set 'n forget, and never need to be changed. The American system had good
group-delay characteristics -- the European did not. So switching channels
could require twisting the hue knob. But that's not all there is to it.
Non-linear group delay changes the colors in a way that cannot be corrected
simply by adjusting the hue control. All the colors cannot be "correct" at
the same time. The advantage of PAL is that these color errors "flip" with
the phase, and are complementary -- the eye "averages" them to the correct
color.
So what's wrong with that? Well, the averaging also reduces saturation.
(Mixing an additive primary with its complement pushes it toward white.)
With severe group-phase error, the image shows bands of varying saturation.
(In NTSC, there are bands of varying hue.)
The other point of confusion is that, for many years, US broadcasters didn't
pay much attention to signal quality. Cameras weren't set up properly, and
burst phase wasn't properly monitored. So when you changed channels, you
sometimes had to change the hue setting. Broadcasters finally got their acts
together, and color quality has, for some time, been pretty consistent from
channel to channel.
In short, PAL's phase alternation is an advantage with transmission systems
having poor group-delay characteristics -- a problem that did not exist in
the US. In every other respect, it is inferior to NTSC.
All of this is true, to the best of my knowledge. Corrections and additions
are welcome.
* Some dishonest manufacturers sold B&W TVs with a "color converter" jack on
the back. It wouldn't have worked, because these sets didn't have the
required IF bandwidth (AFAIK).
** No, the term didn't exist at the time.
*** Some interaction is visible with objects having fine B&W detail. The set
"misinterprets" this detail as color information.
**** This is why two-primary color-movie systems (such as the original
Technicolor) could give acceptable -- though hardly great -- results.
--
"We already know the answers -- we just haven't asked the right
questions." -- Edwin Land
William Sommerwerck
> What about PAL and NTSC videos, DVD/Blu-ray?
> When did they die?
I meant as broadcast systems. I have plenty of NTSC DVDs, and analog cable
signals are still NTSC.
Blu-ray is its own format (1080p/24 or 1080i/60).
Geoffrey S. Mendelson
> What about PAL and NTSC videos, DVD/BluRay? When did they die?
Technically video tapes are not NTSC or PAL. They have separate tracks
for luminance and chroma. The recorders all stripped them apart before
recording them and put them back together when playing them.
There is no technical reason not to build a video player with a digital
output, which digitzes the signals and presents them as an digital data
stream, with out actual NTSC nor PAL encoding. The field/frame rate would
be the same as the source material, but that's not the same thing.
The same with DVD's and BluRay. The data is encoded using MPEG compression,
which has separate information for luminance and chroma. It can be rebuilt
as red-green-blue pixels without ever going through NTSC or PAL.
As reg-green-blue cameras become more common, I expect that there will be
an eventual shift to rgb encoded data, but that's a long way off.
Geoff.
--
Geoffrey S. Mendelson, Jerusalem, Israel g...@mendelson.com N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.
Phil Allison
"William Sommerwanker = Rabid Nut Case "
>
> The belief that NTSC is a stupid design, and PAL corrects all the
> bone-headed elements of NTSC, is untrue. The original NTSC proposal was
> actually PAL (I have the copy of Electronics magazine to prove it), and
> NTSC
> is, overall, a less-compromised design than PAL.
** Wot a putrid pile of utterly absurd verbal sophistry.
The " original NTSC proposal " has got NOTHING to FUCKING do with what
NTSC turned out to be in reality.
In * REALITY * the NTSC broadcast signal is massively compromised in
comparison to a PAL signal.
But on dark, smelly PLANET " Sommerwanker"
- any fucking absurdity is held out to be true.
.... Phil
Phil Allison
"William Sommerwanker Mental Retard "
>>> The belief that NTSC is a stupid design, and PAL corrects
>>> all the bone-headed elements of NTSC, is untrue. The original
>>> NTSC proposal was actually PAL (I have the copy of Electronics
>>> magazine to prove it), and NTSC is, overall, a less-compromised
>>> design than PAL.
>
>> Wot a putrid pile of utterly absurd verbal sophistry.
>
>
>> In * REALITY * the NTSC broadcast signal is massively
>> compromised in comparison to a PAL signal.
>
> You don't know what the hell you're talking about. Put up or shut up.
** YOU have put up nothing but total bollocks.
Everything YOU ever posted is 100% PURE FUCKING BOLLOCKS.
YOU are nothing but a stinking public menace and a VILE narcissistic prick.
Fuck Off and DIE !!!!!!!!!!
William Sommerwerck
> Oh? So Blu-ray will play on a 50 or 60 Hz system
> and the audio will be in sync?
Good question. I haven't looked to see whether a Blu-ray player can be set
to deliver an SD signal. I don't think it can.
Arfa Daily
<snip>
>
> This issue is confused by two factors -- the differences between European
> and American distribution systems, and their studio standards.
>
> If the transmission network has constant group delay, the hue setting
> should
> be set 'n forget, and never need to be changed. The American system had
> good
> group-delay characteristics -- the European did not. So switching channels
> could require twisting the hue knob. But that's not all there is to it.
>
> Non-linear group delay changes the colors in a way that cannot be
> corrected
> simply by adjusting the hue control. All the colors cannot be "correct" at
> the same time. The advantage of PAL is that these color errors "flip" with
> the phase, and are complementary -- the eye "averages" them to the correct
> color.
I don't think that is actually true. It's been a lot of years since I
studied PAL decoding at college, but as far as I recall, the averaging is
done totally electronically, courtesy of the PAL delay line. This is a glass
block delay line of one scan-line period, so if you run a direct and a
delayed path side by side in the chrominance channel, and then sum the
outputs of both, you arrive at an electronically averaged result of two
sequential lines, with any phase errors balanced to zero. This has nil
effect on the overall colour saturation, as this is controlled by a) the ACC
circuit, and b) the user saturation control
>
> So what's wrong with that? Well, the averaging also reduces saturation.
> (Mixing an additive primary with its complement pushes it toward white.)
> With severe group-phase error, the image shows bands of varying
> saturation.
> (In NTSC, there are bands of varying hue.)
>
<snip>
stra...@yahoo.com
wrote:
Not so fast there. 2" quadruplex invented by Ampex in 1956 was a
composite recorder that records the composite signal as analog FM with
no processing at all. It was replaced by SMPTE C 1" helical recorders
which also recorded the composite analog FM signal with no processing.
Sony Betacam was the first recorder that used separate luma/chroma
channels analog FM. This is a little problem when supplied with a
composite input as the luma and chroma has to be separated but when
mounted directly on a camera where the luma and chroma originate it's
very good. D1 digital is a component format with 13.5 MHz luma
sampling and 6.75 MHz chroma channels with no data compression on 19
mm tape. Commonly called 4:2:2. Digital Betacam is the same sample
rate as D1 on a 1/2" tape with 3-1 data compression. This is one of
the most common formats. D-2 digital invented by Ampex for commercial
play is a composite digital machine sampled at 14.3MHz aka 4x
subcarrier on 19mm (3/4") tape. The Sony D-2 machines were much more
successful. Panasonic D-3 digital is 4x subcarrier composite digital
on 1/2" tape. Ampex DCT on 19mm tape is a component digital 4:2:2
machine with 2-1 compression.
So, PAL / NTSC refers to the subcarrier encoding so composite machines
are indeed PAL or NTSC while component machines are not. They are
however referred to as 525 or 625. And yes, all those formats are
still in daily use, the 1" and 2" primarily for dubbing to modern
formats - often digital Beta.
HD machines have options to record all 3 channels at full bandwidth.
This becomes important when compositing images using blue screen or
green screen.
G²
stra...@yahoo.com
PAL has plenty wrong with it and is 'massively compromised' the same
ways as NTSC. Editing in composite PAL is twice as crappy as NTSC
because of the 8 field PAL vs 4 field NTSC color frame sequences. Of
course nobody's done that kind of editing in many years since the
change to digital component in the '90s. Now with HD digital there
isn't any tape as the capture and editing is done in computers -
running (gasp) Windows XP. See Harris Nexio and Velocity.
G²
Sylvia Else
> <snip>
>>
>> This issue is confused by two factors -- the differences between European
>> and American distribution systems, and their studio standards.
>>
>> If the transmission network has constant group delay, the hue setting
>> should
>> be set 'n forget, and never need to be changed. The American system had
>> good
>> group-delay characteristics -- the European did not. So switching channels
>> could require twisting the hue knob. But that's not all there is to it.
>>
>> Non-linear group delay changes the colors in a way that cannot be
>> corrected
>> simply by adjusting the hue control. All the colors cannot be "correct" at
>> the same time. The advantage of PAL is that these color errors "flip" with
>> the phase, and are complementary -- the eye "averages" them to the correct
>> color.
>
> I don't think that is actually true.
I think you'll find that was the intent. However, if the phase error is
too great, the eye averaging doesn't work so well, hence the
introduction of the delay line.
At which point you wonder why bother sending two colour signals in
quadrature if you're just going to average them with the next scan line
anyway. SECAM avoids that complexity by just going straight to the delay
line. I lived in Paris for 18 months. If there's a quality difference
between a SECAM and PAL picture, it was far from obvious.
Sylvia.
Phil Allison
<stra...@yahoo.com
> In * REALITY * the NTSC broadcast signal is massively compromised in
> comparison to a PAL signal.
PAL has plenty wrong with it and is 'massively compromised' the same
ways as NTSC.
** More INSANE CRAPOLOGY !!!!!!!!!!
Editing in composite PAL .....
** More fuckwit, OFF TOPIC CRAPOLOGY !!
See the words " broadcast signal " - fuckhead ???
Even know what it means ???
..... Phil
Dave Plowman (News)
<b0011216-745f-45f6...@b33g2000yqc.googlegroups.com>,
<stra...@yahoo.com> wrote:
> PAL has plenty wrong with it and is 'massively compromised' the same
> ways as NTSC. Editing in composite PAL is twice as crappy as NTSC
> because of the 8 field PAL vs 4 field NTSC color frame sequences. Of
> course nobody's done that kind of editing in many years since the
> change to digital component in the '90s.
Company I worked for in the UK were using component recording (Panasonic
MII - high band like Beta SP) in the early '80s, and low band component
was around for quite some time before that. Although didn't meet UK
broadcast spec for most things, unlike high band. Within a couple of years
it was the main format with 1" relegated to archive use. Next change was
to DigiBeta.
--
*Give me ambiguity or give me something else.
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
William Sommerwerck
>> hue setting should be set 'n forget, and never need to be
>> changed. The American system had good group-delay
>> characteristics -- the European did not. So switching channels
>> could require twisting the hue knob. But that's not all there is to it.
>> Non-linear group delay changes the colors in a way that
>> cannot be corrected simply by adjusting the hue control.
>> All the colors cannot be "correct" at the same time. The
>> advantage of PAL is that these color errors "flip" with
>> the phase, and are complementary -- the eye "averages"
>> them to the correct color.
> I don't think that is actually true. It's been a lot of years since
> I studied PAL decoding at college, but as far as I recall, the
> averaging is done totally electronically, courtesy of the PAL
> delay line. This is a glass block delay line of one scan-line
> period, so if you run a direct and a delayed path side by side
> in the chrominance channel, and then sum the outputs of both,
> you arrive at an electronically averaged result of two sequential
> lines, with any phase errors balanced to zero. This has nil effect
> on the overall colour saturation, as this is controlled by a) the
> ACC circuit, and b) the user saturation control.
The averaging can be done electronically, but there is also some visual
averaging.
I'm not sure you can remove the phase distortion without reducing the
saturation -- all the stuff I've read on PAL says otherwise -- but I won't
press the issue because I haven't thought it through carefully.
William Sommerwerck
> too great, the eye averaging doesn't work so well, hence the
> introduction of the delay line.
> At which point you wonder why bother sending two colour signals in
> quadrature if you're just going to average them with the next scan line
> anyway.
But you don't have to average them. NTSC doesn't. And the delay line can be
used for comb filtering.
> SECAM avoids that complexity by just going straight to the delay
> line. I lived in Paris for 18 months. If there's a quality difference
> between a SECAM and PAL picture, it was far from obvious.
The problem is, SECAM /requires/ the delay line because the system transmits
only the red or blue color-difference signal at any time. This is what I was
talking about -- it keeps the transmission side cheap, while making the user
pay more for their TV.
For most images, you won't see a difference. But in an image with strong
vertical color transitions, you'll see aliasing, especially when the image
moves vertically.
Sylvia Else
If we were building an analogue colour TV transmission infrastructure
now, then maybe we'd go the NTSC route, since it eliminates the delay
line. But it's undoubtedly true that, for whatever reasons, in earlier
times, NTSC didn't perform that well, whereas those whose systems were
PAL or SECAM got good colour pictures from day one.
Sylvia.
Phil Allison
"Stupider than Anyone Else Alive"
> If we were building an analogue colour TV transmission infrastructure now,
> then maybe we'd go the NTSC route, since it eliminates the delay line.
** Total insanity.
> But it's undoubtedly true that, for whatever reasons, in earlier times,
> NTSC didn't perform that well,
** The laws of nature have not changed since 1953
- you tenth witted, know nothing, bullshitting pommy bitch !!!
..... Phil
Sylvia Else
> "Stupider than Anyone Else Alive"
>
>
>> If we were building an analogue colour TV transmission infrastructure now,
>> then maybe we'd go the NTSC route, since it eliminates the delay line.
>
> ** Total insanity.
You realise there are two different delay elements required in a
PAL/SECAM set?
>
>
>> But it's undoubtedly true that, for whatever reasons, in earlier times,
>> NTSC didn't perform that well,
>
>
> ** The laws of nature have not changed since 1953
I think engineering techniques have.
Sylvia.
Phil Allison
>>> If we were building an analogue colour TV transmission infrastructure
>>> now,
>>> then maybe we'd go the NTSC route, since it eliminates the delay line.
>>
>> ** Total insanity.
>
> You realise there are two different delay elements required in a PAL/SECAM
> set?
** Not relevant to the point at all.
>>> But it's undoubtedly true that, for whatever reasons, in earlier times,
>>> NTSC didn't perform that well,
>>
>>
>> ** The laws of nature have not changed since 1953
>
> I think engineering techniques have.
** Not relevant to the point at all.
You TROLLING, ASD fucked, congenital moron !!!!
.... Phil
stra...@yahoo.com
> <stratu...@yahoo.com
They still do some composite D-2 editing at CBS network. Or don't they
count as broadcast?
G²
Phil Allison
<stra...@yahoo.com>
> ** More fuckwit, OFF TOPIC CRAPOLOGY !!
>
> See the words " broadcast signal " - fuckhead ???
>
> Even know what it means ???
>
They still do some composite D-2 editing at CBS network. Or don't they
count as broadcast?
** Hey fuckwit.
In relation to television transmission - where does one find the "
broadcast signal " ???
Don't strain you tiny brain thinking too hard.
..... Phil
isw
Sylvia Else <syl...@not.at.this.address> wrote:
And had high-brightness flicker for just as long...
Isaac
Sylvia Else
> If the transmission network has constant group delay, the hue setting should
> be set 'n forget, and never need to be changed.
It's not clear to me why that wasn't the case anyway. Whatever phase
error was introduced to the colour signal by the transmission system
would also affect the colour burst. If the problem could be addressed by
means of a tint control with a setting that remained stable even over
the duration of a program, it rather seems to imply that a phase error
between the colour burst and the colour subcarrier was built into the
signal at the studio.
Sylvia.
Michael A. Terrell
isw wrote:
>
> > Sylvia Else wrote:
> >
> > If we were building an analogue colour TV transmission infrastructure
> > now, then maybe we'd go the NTSC route, since it eliminates the delay
> > line.
NTSC? No delay line? Moron. The luminance data had to be delayed to
allow time to process the Chroma data. An open delay line in a NTSC
video display caused a very dark image with moving blotches of color. I
found and replaced several, in NTSC TVs and Video Monitors.
--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'
Sylvia Else
>
> isw wrote:
>>
>>> Sylvia Else wrote:
>>>
>>> If we were building an analogue colour TV transmission infrastructure
>>> now, then maybe we'd go the NTSC route, since it eliminates the delay
>>> line.
>
>
> NTSC? No delay line? Moron. The luminance data had to be delayed to
> allow time to process the Chroma data. An open delay line in a NTSC
> video display caused a very dark image with moving blotches of color. I
> found and replaced several, in NTSC TVs and Video Monitors.
>
>
In which case you'd know that a PAL TV contains two delay lines. One
provides a short delay and addresses the difference in delay between the
chroma path and the luminance path. The other provides a full scan line
delay to allow averaging of the chrominance signal.
It should be obvious from context that "the" delay line that I was
referring to was the latter.
But I suppose calling people morons is easier than doing your own thinking.
Sylvia.
David
"Sylvia Else" <syl...@not.at.this.address> wrote in message
news:4bb6f524$0$1483$c3e...@news.astraweb.com...
One big problem was differential phase and gain in the
transmission path. In this case both the amplitude and phase
of the color information was influenced by the total
amplitude of the signal including the luminance. Since the
burst was at IRE 0 and the average picture content was IRE
50 or so, differential phase shifted the color hue.
David
William Sommerwerck
> infrastructure now, then maybe we'd go the NTSC route,
> since it eliminates the delay line.
PAL doesn't /require/ a delay line.
> But it's undoubtedly true that, for whatever reasons, in earlier
> times, NTSC didn't perform that well, whereas those whose
> systems were PAL or SECAM got good colour pictures from
> day one.
NTSC has always "performed well". Poor NTSC image quality was always due to
bad studio practice.
William Sommerwerck
That's really going too far. Is there any way to permanently block Mr.
Allison?
By the way, it's pome, an acronym of "prisoner of mother England".
William Sommerwerck
>> now, then maybe we'd go the NTSC route, since it eliminates the delay
>> line.
> NTSC? No delay line? Moron. The luminance data had to be delayed to
> allow time to process the Chroma data. An open delay line in a NTSC
> video display caused a very dark image with moving blotches of color. I
> found and replaced several, in NTSC TVs and Video Monitors.
She's talking about phase averaging (or whatever it's called -- I don't know
the term).
The delay line /you're/ talking about is required in NTSC and PAL receivers,
because the narrower-band color signal(s) have greater group delay, and the
luminance has to be "slowed down" to match.
William Sommerwerck
We're talking about non-linear group delay. This is not a simple phase error
in the burst, but a non-time-constant delay across the bandwidth of the
chroma signal. Any such non-linear delay will introduce varying color errors
that cannot be corrected with a single hue setting.
Phil Allison
"William Sommerwanker FUCKING TROLL "
> Phil Allison
>>
>> ** The laws of nature have not changed since 1953
> That's really going too far.
** Really ??????????????
Which laws of nature have changed since 1953 ?
Please give all relevant details.
Or I will FUCK you right off usenet for ever -
you vile, stinking, pile of sub human autistic SHIT !!
..... Phil
Phil Allison
"William Sommerwanker LYING TROLL "
> NTSC has always "performed well".
** MASSIVE LIE .
> Poor NTSC image quality was always due to
> bad studio practice.
** Another MASSIVE LIE.
.... Phil
>
>
Phil Allison
"William Sommerwanker LYING FUCKWIT TROLL "
> NTSC has always "performed well".
** MASSIVE LIE .
> Poor NTSC image quality was always due to
> bad studio practice.
** Another MASSIVE LIE.
FOAD you stupid old CUNT !!
.... Phil
Phil Allison
"William Sommerwanker LYING TROLL "
> NTSC has always "performed well".
** MASSIVE LIE .
> Poor NTSC image quality was always due to
> bad studio practice.
** Another MASSIVE LIE.
FOAD you stupid old AUTISTIC CUNT !!
.... Phil
Sylvia Else
But, as you say, that kind of problem cannot be corrected with a single
hue setting, so no amount of fiddling with the tint control would have
produced an acceptable picture, even over a short timescale.
I understand that prior to the expiry of the Telefunken PAL patent, Sony
Trinitron sets for the PAL market actually threw away the chrominance
signal on alternate scan lines, thus landing themselves back in NTSC
territory. Those sets had a tint control, and I know from personal
experience that they produced a perfectly satisfactory result (I only
learnt the other day why they had a tint control).
So even if non-linear delay was a theoretical problem, it appears not to
have been one in practice. At least, not in the UK.
Sylvia.
David Nebenzahl
>> ** The laws of nature have not changed since 1953
>> - you tenth witted, know-nothing, bullshitting pommy bitch !!!
>
> That's really going too far. Is there any way to permanently block Mr.
> Allison?
You're not serious, are you? I mean, I'm sure you already know the
answer to that question.
My suggestion: enjoy the Phil Allison Ride while it's running. Wheee!
--
You were wrong, and I'm man enough to admit it.
- a Usenet "apology"
stra...@yahoo.com
What the heck has the transmitter got to do with it? Anything that is
right or wrong with an NTSC signal is equally right or wrong BEFORE
the transmitter. The transmitter is just a way to get the signal to
lots of folks at once. Or does that confuse YOU?
G²
Phil Allison
<stra...@yahoo.com>
"Phil Allison"
>
> > ** More fuckwit, OFF TOPIC CRAPOLOGY !!
>
> > See the words " broadcast signal " - fuckhead ???
>
> > Even know what it means ???
>
> They still do some composite D-2 editing at CBS network. Or don't they
> count as broadcast?
>
> ** Hey fuckwit.
>
> In relation to television transmission - where does one find the "
> broadcast signal " ???
>
> Don't strain you tiny brain thinking too hard.
What the heck has the transmitter got to do with it?
** I made no mention of any " transmitter"
- you FUCKING ILLITERATE MORON !!!
The fuckwit still no idea where a " broadcast signal" is to be found.
Cos obviously, this asinine cunthead has no clue why engineers were
motivated to develop PAL in the first place.
..... Phil
stra...@yahoo.com
Because people like you couldn't figure out how to use NTSC?
G²
Phil Allison
** More fuckwit, OFF TOPIC CRAPOLOGY !!
> See the words " broadcast signal " - fuckhead ???
>
> > Even know what it means ???
>
> They still do some composite D-2 editing at CBS network. Or don't they
> count as broadcast?
>
> ** Hey fuckwit.
>
> In relation to television transmission - where does one find the "
> broadcast signal " ???
>
> Don't strain you tiny brain thinking too hard.
What the heck has the transmitter got to do with it?
** I made no mention of any " transmitter"
- you FUCKING ILLITERATE MORON !!!
This fuckwit still no idea where a " broadcast signal" is to be found !!
What a FUCKING MORON !!!!!!!!!!!!!!!!!!
Obviously, this asinine ASD fucked cunt has no clue why engineers were
Dave Plowman (News)
Sylvia Else <syl...@not.at.this.address> wrote:
> I understand that prior to the expiry of the Telefunken PAL patent, Sony
> Trinitron sets for the PAL market actually threw away the chrominance
> signal on alternate scan lines, thus landing themselves back in NTSC
> territory. Those sets had a tint control, and I know from personal
> experience that they produced a perfectly satisfactory result (I only
> learnt the other day why they had a tint control).
Depends on what you mean by 'satisfacory'. Passable, maybe.
--
*Verbs HAS to agree with their subjects *
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
isw
<b463273f-75d6-4957...@l36g2000yqb.googlegroups.com>,
stra...@yahoo.com wrote:
You are evidently not aware that a poorly designed or operated
transmitter can introduce all sorts of distortions to the signal. Talk
to the engineers who designed or operated them sometime.
Isaac
Phil Allison
"isw"
> stra...@yahoo.com wrote:
>
>
>> What the heck has the transmitter got to do with it? Anything that is
>> right or wrong with an NTSC signal is equally right or wrong BEFORE
>> the transmitter. The transmitter is just a way to get the signal to
>> lots of folks at once. Or does that confuse YOU?
>
> You are evidently not aware that a poorly designed or operated
> transmitter can introduce all sorts of distortions to the signal. Talk
> to the engineers who designed or operated them sometime.
>
** Maybe you can tell this utter imbecile what the phrase " broadcast signal
" refers to ??
..... Phil
William Sommerwerck
>> Sony Trinitron sets for the PAL market actually threw away the
>> chrominance signal on alternate scan lines, thus landing themselves
>> back in NTSC territory. Those sets had a tint control, and I know from
>> personal experience that they produced a perfectly satisfactory result
>> (I only learnt the other day why they had a tint control).
> Depends on what you mean by "satisfactory". Passable, maybe.
When you discuss something at length, you become aware of those things you
thought you understood, but didn't. (Well, I do, anyway.)
I'd always read that one could construct a PAL receiver in such a way that
eliminated the need for a manual hue control. I never questioned this, but
now it makes little sense.
There are two reasons for having a manual hue control:
>> The user can adjust the color rendition to their personal (and usually
incorrect) taste. *
>> The user can correct for incorrect burst phase.
That seems to be "it". As we've seen, these errors can be corrected by
adjusting the hue control, whereas the other error -- differential phase
shift -- cannot be so-corrected, because the timing errors are not linear.
Here's where I get confused. The line-to-line polarity reversal ** causes
the differential phase errors to be equal and opposite, and thus cancel out
when added (at the cost of desaturation -- but that's another issue).
However... If the burst phase is wrong, then there is no cancellation of
errors, because there are no "errors" /in the signal itself/. (Right? (???))
Therefore, I don't see how line averaging can be used to eliminate the need
for a manual hue control.
If anyone knows of a reference with a non-tautological explanation, I'd
appreciate a pointer to it. Thanks.
* Left to their own devices, the average user generally sets the color for
greenish skin tones. I wonder if Vulcan viewers tended towards a pinkish
error.
** It's actually line-to-line+2, because the image is interlaced.
Dave Plowman (News)
William Sommerwerck <grizzle...@comcast.net> wrote:
> >> I understand that prior to the expiry of the Telefunken PAL patent,
> >> Sony Trinitron sets for the PAL market actually threw away the
> >> chrominance signal on alternate scan lines, thus landing themselves
> >> back in NTSC territory. Those sets had a tint control, and I know from
> >> personal experience that they produced a perfectly satisfactory result
> >> (I only learnt the other day why they had a tint control).
> > Depends on what you mean by "satisfactory". Passable, maybe.
> When you discuss something at length, you become aware of those things
> you thought you understood, but didn't. (Well, I do, anyway.)
> I'd always read that one could construct a PAL receiver in such a way
> that eliminated the need for a manual hue control. I never questioned
> this, but now it makes little sense.
I've never seen a set designed for the PAL market with a hue control. Only
ones modified from a basically NTSC design.
> There are two reasons for having a manual hue control:
> >> The user can adjust the color rendition to their personal (and
> >> usually incorrect) taste. *
> >> The user can correct for incorrect burst phase.
> That seems to be "it". As we've seen, these errors can be corrected by
> adjusting the hue control, whereas the other error -- differential phase
> shift -- cannot be so-corrected, because the timing errors are not
> linear.
You simply don't get hue errors on PAL sets - unless the grey scale is set
incorrectly. Of course some sets also used the incorrect phosphors to
provide a brighter picture - but a hue control couldn't compensate for
that.
--
*I'm already visualizing the duct tape over your mouth
Sylvia Else
Think of the chroma signal as a vector with its y coordinate equal the
red difference component, and the x coordinate equal to the blue
difference component. A phase error rotates that vector about the z
axis. Effectively, the blue difference component receives a bit of the
red difference component, and vice versa.
On alternate lines the phase of the red difference component *only* is
inverted. In our view, this has the effect of reflecting the vector in
the x axis - what was a positive y value becomes negative.
The same phase error causes this vector to rotate in the same direction
about the z axis, but because of the reflection, the mixing of the
components has the opposite sign.
If you then negate the resulting red difference component of the second
line, and average with the red difference component of the first line,
the parts received from the blue difference component cancel out,
leaving a red different component that equals the original, multiplied
by the cosine of the phase error. The same applies to the blue
component. The result is that the hues are correct, but not as saturated
as they shoud have been.
Sylvia.
William Sommerwerck
>> errors, because there are no "errors" /in the signal itself/. (Right?
(???))
>> Therefore, I don't see how line averaging can be used to eliminate the
need
>> for a manual hue control.
> Think of the chroma signal as a vector with its y coordinate equal the
> red difference component, and the x coordinate equal to the blue
> difference component. A phase error rotates that vector about the z
> axis. Effectively, the blue difference component receives a bit of the
> red difference component, and vice versa.
> On alternate lines the phase of the red difference component *only* is
> inverted. In our view, this has the effect of reflecting the vector in
> the x axis - what was a positive y value becomes negative.
> The same phase error causes this vector to rotate in the same direction
> about the z axis, but because of the reflection, the mixing of the
> components has the opposite sign.
> If you then negate the resulting red difference component of the second
> line, and average with the red difference component of the first line,
> the parts received from the blue difference component cancel out,
> leaving a red different component that equals the original, multiplied
> by the cosine of the phase error. The same applies to the blue
> component. The result is that the hues are correct, but not as saturated
> as they shoud have been.
No argument. That's always been my understanding. But...
If the burst phase gets screwed up somewhere along the line, no amount of
line averaging will fix the problem, because there's nothing "wrong" with
the subcarrier to fix.
Granted, this problem hardly ever happens. But the argument that a fully
implemented PAL set is inherently immune to color errors is hard for me to
swallow.
Geoffrey S. Mendelson
> If you then negate the resulting red difference component of the second
> line, and average with the red difference component of the first line,
> the parts received from the blue difference component cancel out,
> leaving a red different component that equals the original, multiplied
> by the cosine of the phase error. The same applies to the blue
> component. The result is that the hues are correct, but not as saturated
> as they shoud have been.
Since PAL TV sets have a saturation (color level) control, isn't that
a "non-problem". If it matters, you just adjust it to compensate.
My experience is that people set the color saturation too high, if I hold
my hand up to the screen my skin looks pale in comparison to everyone
on it.
Geoff.
--
Geoffrey S. Mendelson, Jerusalem, Israel g...@mendelson.com N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.
Dave Plowman (News)
Geoffrey S. Mendelson <g...@cable.mendelson.com> wrote:
> My experience is that people set the color saturation too high, if I hold
> my hand up to the screen my skin looks pale in comparison to everyone
> on it.
Especially CSI. ;-)
--
*If I throw a stick, will you leave?
Geoffrey S. Mendelson
> In article <slrnhrjv4...@cable.mendelson.com>,
> Geoffrey S. Mendelson <g...@cable.mendelson.com> wrote:
>> My experience is that people set the color saturation too high, if I hold
>> my hand up to the screen my skin looks pale in comparison to everyone
>> on it.
>
> Especially CSI. ;-)
That's funny, I was thinking of last Thursday night's episode of CSI
when I wrote that.
Sylvia Else
If the burst has a random phase relationship to the colour subcarrier on
each line, then my analysis falls apart because the vectors would have
random orientations. In such a situation a PAL receiver would do no
better than NTSC, and they'd both perform awfully.
If the burst just has a fixed phase offset from the true colour
subcarrier, then the averaging will work.
Indeed it will work if the colour subcarrier drifts in a consistent way
relative to the burst - or if the receiver's oscillator similarly
drifts. The effect of such a drift on an NSTC picture would be a
variation of tint from left to right. However, a tint control wouldn't
be able to address that problem - it would simply move the horizontal
position on the screen where the colours are accurate - suggesting that
it doesn't occur in practice except in equipment that is recognisably
broken.
>
> Granted, this problem hardly ever happens. But the argument that a fully
> implemented PAL set is inherently immune to color errors is hard for me to
> swallow.
>
>
I don't think there's a claim that it is inherently immune to all colour
errors, only those caused by consistent differences between the phase of
the subcarrier and the burst.
Sylvia.
Sylvia Else
> Sylvia Else wrote:
>> If you then negate the resulting red difference component of the second
>> line, and average with the red difference component of the first line,
>> the parts received from the blue difference component cancel out,
>> leaving a red different component that equals the original, multiplied
>> by the cosine of the phase error. The same applies to the blue
>> component. The result is that the hues are correct, but not as saturated
>> as they shoud have been.
>
> Since PAL TV sets have a saturation (color level) control, isn't that
> a "non-problem". If it matters, you just adjust it to compensate.
If it's a fixed phase error, yes. If the phase error is changing slowly
over time the the picture will have a saturation that varies over time
which would be annoying if the effect were high enough.
However, I've never noticed such an effect.
Sylvia.
William Sommerwerck
> subcarrier, then the averaging will work.
Right. I missed that.
> I don't think there's a claim that [PAL] is inherently immune to
Arfa Daily
"Sylvia Else" <syl...@not.at.this.address> wrote in message
news:4bba994c$0$15459$c3e...@news.astraweb.com...
Many years back, Bush in the UK produced a colour decoder which was
'revolutionary' compared to other manufacturers' efforts, in that the
subcarrier was regenerated in the decoder directly from the burst, rather
than being a free-running oscillator just locked to the burst with a PLL.
They did this by deriving a phase-adjustable pulse from the H-flyback, and
using this to 'notch out' the burst from the back porch period. The 10
cycles of burst thus recovered, were then applied directly to the 4.43MHz
crystal, which caused it to ring at exactly the same frequency and in
exactly the same phase as the original subcarrier. Always seemed to work
pretty well, and they continued to use this system over a period of probably
10 years or more, covering three chassis designs / revisions.
Arfa
Arfa Daily
"Sylvia Else" <syl...@not.at.this.address> wrote in message
I would guess that you never would see such an effect, as all of the
decoders that I can remember working on, had ACC circuits which worked very
well ...
Arfa
William Sommerwerck
> 'revolutionary' compared to other manufacturers' efforts, in that the
> subcarrier was regenerated in the decoder directly from the burst, rather
> than being a free-running oscillator just locked to the burst with a PLL.
> They did this by deriving a phase-adjustable pulse from the H-flyback, and
> using this to 'notch out' the burst from the back porch period. The 10
> cycles of burst thus recovered, were then applied directly to the 4.43MHz
> crystal, which caused it to ring at exactly the same frequency and in
> exactly the same phase as the original subcarrier. Always seemed to work
> pretty well, and they continued to use this system over a period of
> probably 10 years or more, covering three chassis designs / revisions.
This was first done by GE, circa 1966, in the Portacolor set, mostly because
it was cheaper.
Another way of looking at this system is that the crystal was an extremely
narrow-band filter that removed the "Fourier sidebands" around the
subcarrier frequency created by transmitting the 10-cycle burst only once on
each scanning line.
Michael A. Terrell
>
> On 3/04/2010 10:04 PM, Michael A. Terrell wrote:
> >
> > isw wrote:
> >>
> >>> Sylvia Else wrote:
> >>>
> >>> now, then maybe we'd go the NTSC route, since it eliminates the delay
> >>> line.
> >
> >
> > NTSC? No delay line? Moron. The luminance data had to be delayed to
> > allow time to process the Chroma data. An open delay line in a NTSC
> > video display caused a very dark image with moving blotches of color. I
> > found and replaced several, in NTSC TVs and Video Monitors.
> >
> >
>
> In which case you'd know that a PAL TV contains two delay lines. One
> provides a short delay and addresses the difference in delay between the
> chroma path and the luminance path. The other provides a full scan line
> delay to allow averaging of the chrominance signal.
>
> It should be obvious from context that "the" delay line that I was
> referring to was the latter.
>
> But I suppose calling people morons is easier than doing your own thinking.
It is, for people who consider one as zero.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.
Michael A. Terrell
Central Florida
Sylvia Else
I'm left wondering what exactly was the *real* problem that PAL was
intended to fix. It appears that the NTSC tint control could only
address a fixed phase offset between the colour burst and the
subcarrier, with both transmitters and TV sets able to maintain that
offset sufficiently closely that the hue wouldn't vary from left to
right of the picture.
Other issues, such as non-linear phase shift would have been a problem
for NTSC viewers, regardless of the tint control.
So were NTSC viewers tolerating colour pictures that couldn't be set
right even with the tint control? Or is there something else that I've
missed?
Sylvia.
isw
Sylvia Else <syl...@not.at.this.address> wrote:
--snippety-snip--
> I'm left wondering what exactly was the *real* problem that PAL was
> intended to fix.
Political. The Europeans didn't want US companies selling sets there.
Isaac
Dave Plowman (News)
> --snippety-snip--
Didn't stop the Japanese, etc. But US companies would have to do other
mods to their products for European sales anyway. Like mains voltage and
frequency. Most couldn't be bothered - even when that's all which had to
be changed.
--
*Letting a cat out of the bag is easier than putting it back in *
William Sommerwerck
> was intended to fix. It appears that the NTSC tint control could
> only address a fixed phase offset between the colour burst and
> the subcarrier, with both transmitters and TV sets able to
> maintain that offset sufficiently closely that the hue wouldn't
> vary from left to right of the picture.
Correct.
> Other issues, such as non-linear phase shift would have been
> a problem for NTSC viewers, regardless of the tint control.
Also correct.
> So were NTSC viewers tolerating colour pictures that couldn't
> be set right even with the tint control? Or is there something
> else that I've missed?
You /have/ missed something, which I explained "long ago and far away".
<grin>
The US TV-distribution system DID NOT generally suffer from non-linear
group-delay problems, whereas the European system DID. That's it.
Even without the extra delay line, there is some degree of visual color
averaging, which tends to mitigate the phase error.
William Sommerwerck
>> sets there.
> Didn't stop the Japanese, etc. But US companies would have
> to do other mods to their products for European sales anyway.
> Like mains voltage and frequency. Most couldn't be bothered --
> even when that's all which had to be changed.
I don't buy that. US sets would have been fairly expensive in Europe, even
in the mid-60s. Not to mention the strong competition from Thomson, Philips,
etc.
PeterD
Part of the difficulity in understanding is that perhaps you don't
have experience with early American color televisions... I certainly
remember how in the 60s we had to adjust the tint control on a regular
(show by show) basis, because of lack of consistancy.
Today, with predominatly digital systems, it has been so long since
I've touched a tint control, that I wonder if they still exist!
Anyone who had one of those old, tube (valve) color sets, with the 21"
round color CRT, will remember seeing green skies, and blue grass
while having skin colors set to the proper shade. Get the sky blue,
and the skin turned red, or blue, or green!
William Sommerwerck
> don't have experience with early American color televisions...
> I certainly remember how in the 60s we had to adjust the tint
> control on a regular (show by show) basis, because of lack
> of consistancy.
Yes -- a lack of consistency. That was not the fault of NTSC, but of the
broadcasters.
> Anyone who had one of those old, tube (valve) color sets,
> with the 21" round color CRT, will remember seeing green
> skies, and blue grass while having skin colors set to the
> proper shade. Get the sky blue, and the skin turned red,
> or blue, or green!
I don't think that's correct. The cameras (and/or encoders) would have had
to have been very badly set up for that to happen.
On a related subject... I remember reading long, long ago that the first RCA
color TV had /four/ controls for adjusting the color, which the author
described as a "combination lock"! Anyone know anything about this?
Sylvia Else
>> I'm left wondering what exactly was the *real* problem that PAL
>> was intended to fix. It appears that the NTSC tint control could
>> only address a fixed phase offset between the colour burst and
>> the subcarrier, with both transmitters and TV sets able to
>> maintain that offset sufficiently closely that the hue wouldn't
>> vary from left to right of the picture.
>
> Correct.
>
>
>> Other issues, such as non-linear phase shift would have been
>> a problem for NTSC viewers, regardless of the tint control.
>
> Also correct.
>
>
>> So were NTSC viewers tolerating colour pictures that couldn't
>> be set right even with the tint control? Or is there something
>> else that I've missed?
>
> You /have/ missed something, which I explained "long ago and far away".
> <grin>
OK, I vaguely remember your saying that now.
In the UK, colour was only transmitted on a new 625 line service
(newish, in the case of BBC2), in parallel for a long time with a
monochrome 405 line service (except BBC2), and I'd have thought the new
transmission infrastructure could have been built to obviate the
non-linear group-delay, given that it existed in the USA.
And, as I commented before, the Sony Trinitron sets, which didn't
implement PAL, performed acceptably according to my memory.
Sylvia.
Sylvia Else
>> Part of the difficulity in understanding is that perhaps you
>> don't have experience with early American color televisions...
>> I certainly remember how in the 60s we had to adjust the tint
>> control on a regular (show by show) basis, because of lack
>> of consistancy.
>
> Yes -- a lack of consistency. That was not the fault of NTSC, but of the
> broadcasters.
I have to wonder what the broadcasters were doing to achieve that.
Contriving to get the colour burst phase consistent amongst cameras in a
studio (so that the tint stayed the same for a show), but inconsistent
with the actual colour subcarrier, would take some doing.
Sylvia.
William Sommerwerck
> service (newish, in the case of BBC2), in parallel for a long
> time with a monochrome 405 line service (except BBC2),
> and I'd have thought the new transmission infrastructure
> could have been built to obviate the non-linear group-delay,
> given that it existed in the USA.
You're probably correct.
William Sommerwerck
>> of NTSC, but of the broadcasters.
> I have to wonder what the broadcasters were doing to achieve
> that. Contriving to get the colour burst phase consistent amongst
> cameras in a studio (so that the tint stayed the same for a show),
> but inconsistent with the actual colour subcarrier, would take
> some doing.
There is no subcarrier or burst signal in the cameras. They aren't needed at
that point, and are added during the encoding process.
Setting them up is another matter. The early episodes of "Barney Miller"
provide a good example of poor setup, with inconsistent color, and poor
convergence.
Sylvia Else
>>> Yes -- a lack of consistency. That was not the fault
>>> of NTSC, but of the broadcasters.
>
>> I have to wonder what the broadcasters were doing to achieve
>> that. Contriving to get the colour burst phase consistent amongst
>> cameras in a studio (so that the tint stayed the same for a show),
>> but inconsistent with the actual colour subcarrier, would take
>> some doing.
>
> There is no subcarrier or burst signal in the cameras. They aren't needed at
> that point, and are added during the encoding process.
Ok, so the separate colour signals (and luminance?) are sent from the
cameras. Still, at some point the colour signals have to be encoded
using the colour subcarrier, and a bit of the latter has to be included
as the burst. Failing to keep them in phase would require a considerable
amount of indifference.
Which I think you've also said ;)
>
> Setting them up is another matter. The early episodes of "Barney Miller"
> provide a good example of poor setup, with inconsistent color, and poor
> convergence.
>
Poor convergence? The mind boggles.
Sylvia.
Michael A. Terrell
William Sommerwerck wrote:
>
> > Part of the difficulity in understanding is that perhaps you
> > don't have experience with early American color televisions...
> > I certainly remember how in the 60s we had to adjust the tint
> > control on a regular (show by show) basis, because of lack
> > of consistancy.
>
> Yes -- a lack of consistency. That was not the fault of NTSC, but of the
> broadcasters.
And AT&T who provided the coaxial cables that fed the video to all
the stations on a network. The tint and chroma level could be adjusted
at every facility in the system. I knew someone who worked for AT&T at
the time, and he told me what a pain it was to compensate for the
cable. When the network switched to a different studio or city for a
show, it threw everything out of calibration.
> > Anyone who had one of those old, tube (valve) color sets,
> > with the 21" round color CRT, will remember seeing green
> > skies, and blue grass while having skin colors set to the
> > proper shade. Get the sky blue, and the skin turned red,
> > or blue, or green!
>
> I don't think that's correct. The cameras (and/or encoders) would have had
> to have been very badly set up for that to happen.
>
> On a related subject... I remember reading long, long ago that the first RCA
> color TV had /four/ controls for adjusting the color, which the author
> described as a "combination lock"! Anyone know anything about this?
He may be talking about the three 'drive' controls that set the gain
for each channel. These are set up to provide equal gain to get a white
line during setup. They are service adjustments on TVs, but on an early
design they may have been easier to get to. Some TVs still had hollow
plastic shaft extenders that passed through the rear of floor model
cabinets to adjust these and other pots.
The fourth would be the actual dolor intensity control.
--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'
William Sommerwerck
>> "Barney Miller" provide a good example of poor setup, with
>> inconsistent color, and poor convergence.
> Poor convergence? The mind boggles.
Oh, yes. The pickups had to be aligned. The "modern" system, in which
solid-state sensors are attached to a prism/beamsplitter was not practical
with vidicons and Plumbicons.
William Sommerwerck
>> that the first RCA color TV had /four/ controls for adjusting
>> the color, which the author described as a "combination lock"!
>> Anyone know anything about this?
> He may be talking about the three 'drive' controls that set the
> gain for each channel. These are set up to provide equal gain
> to get a white line during setup. They are service adjustments
> on TVs, but on an early design they may have been easier to get to.
No, these were supposedly user controls. Anybody got a photo of the user
controls for a CT-100?
Dave Plowman (News)
William Sommerwerck <grizzle...@comcast.net> wrote:
> There is no subcarrier or burst signal in the cameras. They aren't
> needed at that point, and are added during the encoding process.
> Setting them up is another matter. The early episodes of "Barney Miller"
> provide a good example of poor setup, with inconsistent color, and poor
> convergence.
So camera setup was poor - as was the later stages of transmission?
This certainly wasn't the case in the UK - despite the transmitters being
fed with land lines.
--
*Where do forest rangers go to "get away from it all?"
Dave Plowman (News)
Registration on cameras. Convergence on monitors?
Did you have videcon colour cameras? First UK ones were plumbicon. Apart
from the ancient IO RCA ones used for tests.
--
*24 hours in a day ... 24 beers in a case ... coincidence? *
William Sommerwerck
Yes. Thanks for the correction.
> Did you have videcon colour cameras? First UK ones
> were Plumbicon.
Yes, because you started so late.
The first RCA cameras used vidicons (I think) -- though they might have used
image orhticons.
They later had a four-pickup camera that used an image orthicon to generate
a perfectly registered (by definition) luminance signal, plus three
vidicons.
Michael A. Terrell
Local stations weren't immune, either. Some locally produced shows
in Dayton, ohio aired from poorly converged cameras in the '70s & '80s
Dave Plowman (News)
William Sommerwerck <grizzle...@comcast.net> wrote:
> > Registration on cameras. Convergence on monitors?
> Yes. Thanks for the correction.
> > Did you have videcon colour cameras? First UK ones
> > were Plumbicon.
> Yes, because you started so late.
> The first RCA cameras used vidicons (I think) -- though they might have
> used image orhticons.
Three 3 inch IO were the ones I remember. Being used for tests long before
colour broadcasting started in the UK.
> They later had a four-pickup camera that used an image orthicon to
> generate a perfectly registered (by definition) luminance signal, plus
> three vidicons.
That's a configuration I never saw. The first colour cameras here were all
four tube plumblicons. I was taught the colour response of a videcon
wasn't suitable.
BTW I'm not surprised your setup engineers had problems - with a mixture
of IO and videcon. ;-)
--
*Santa's helpers are subordinate clauses*
Michael A. Terrell
"Dave Plowman (News)" wrote:
>
> In article <hpibre$pjs$1...@news.eternal-september.org>,
> William Sommerwerck <grizzle...@comcast.net> wrote:
> > > Registration on cameras. Convergence on monitors?
>
> > Yes. Thanks for the correction.
>
> > > Did you have videcon colour cameras? First UK ones
> > > were Plumbicon.
>
> > Yes, because you started so late.
>
> > The first RCA cameras used vidicons (I think) -- though they might have
> > used image orhticons.
>
> Three 3 inch IO were the ones I remember. Being used for tests long before
> colour broadcasting started in the UK.
>
> > They later had a four-pickup camera that used an image orthicon to
> > generate a perfectly registered (by definition) luminance signal, plus
> > three vidicons.
>
> That's a configuration I never saw. The first colour cameras here were all
> four tube plumblicons. I was taught the colour response of a videcon
> wasn't suitable.
RCA built their TK44 color studio cameras with Vidicons. They
changed the model number to TK46 when they switched to Plumicons. Most
of the parts were interchangeable, so I used a pair of TK44 cameras for
spare modules & as a test jig to keep three TK46 cameras working the way
we wanted. The TK44s were used by TV stations for years, but needed
brighter studio lighting.
isw
"Dave Plowman (News)" <da...@davenoise.co.uk> wrote:
> In article <isw-55C6A6.19545706042010@[216.168.3.50]>,
> isw <i...@witzend.com> wrote:
> > In article <4bbbee16$0$24357$c3e...@news.astraweb.com>,
> > Sylvia Else <syl...@not.at.this.address> wrote:
>
> > --snippety-snip--
>
> > > I'm left wondering what exactly was the *real* problem that PAL was
> > > intended to fix.
>
> > Political. The Europeans didn't want US companies selling sets there.
>
> Didn't stop the Japanese, etc.
But *they* wanted to sell sets *here*.
Isaac
isw
"William Sommerwerck" <grizzle...@comcast.net> wrote:
> > Registration on cameras. Convergence on monitors?
>
> Yes. Thanks for the correction.
>
>
> > Did you have videcon colour cameras? First UK ones
> > were Plumbicon.
>
> Yes, because you started so late.
>
> The first RCA cameras used vidicons (I think) -- though they might have used
> image orhticons.
Iconoscope first, then orthicon, then image orthicon. Vidicons were
first used for film chains, and later as the color (as opposed to
luminance) pickups in *some* cameras.
Isaac
stra...@yahoo.com
wrote:
> "Dave Plowman (News)" wrote:
>
> > In article <hpibre$pj...@news.eternal-september.org>,
I thought TK-44s had plumbs. I _know_ that TK-45s had plumbs as I have
a used one from a TK-45. The TK-28 film camera had vidicons but AIUI,
the vidicon had its own level non-linearity that was not present in
plumbicons (Leddicons for you EEV fans) or Saticons. Vidicons required
different electronic gamma to achieve an overall gamma of 2 to 2.2.
For a film camera the vidicon issue wasn't as bad as the light levels
were much more predicable. You can look at some of the dinosaurs here.
http://www.oldradio.com/archives/hardware/TV/RCA-TV.htm
G²
Michael A. Terrell
There were conversion kits, according to the manuals I had for the
44s
> I _know_ that TK-45s had plumbs as I have
> a used one from a TK-45. The TK-28 film camera had vidicons but AIUI,
> the vidicon had its own level non-linearity that was not present in
> plumbicons (Leddicons for you EEV fans) or Saticons. Vidicons required
> different electronic gamma to achieve an overall gamma of 2 to 2.2.
> For a film camera the vidicon issue wasn't as bad as the light levels
> were much more predicable.
That was why you needed more light in the studio for the Vidicons. It
pushed them into a more linear area of operation. The savings on
lighting costs and air conditioning quickly paid the conversion costs.
The ones we had were from a private studio used a few times a year, to
make commercials by an eccentric old man.
> You can look at some of the dinosaurs here.
>
> http://www.oldradio.com/archives/hardware/TV/RCA-TV.htm
Dave Plowman (News)
Are you saying there were iconoscope colour cameras actually in use?
Videcon monochrome cameras were used for some types of broadcast in the UK
for many a year. Gave very nice pictures with enough light - but didn't
cope with fast movement well.
--
*Sorry, I don't date outside my species.
Dave Plowman (News)
<ef738ef2-efc9-4f66...@v20g2000yqv.googlegroups.com>,
<stra...@yahoo.com> wrote:
> I thought TK-44s had plumbs. I _know_ that TK-45s had plumbs as I have
> a used one from a TK-45. The TK-28 film camera had vidicons but AIUI,
> the vidicon had its own level non-linearity that was not present in
> plumbicons (Leddicons for you EEV fans) or Saticons. Vidicons required
> different electronic gamma to achieve an overall gamma of 2 to 2.2.
> For a film camera the vidicon issue wasn't as bad as the light levels
> were much more predicable. You can look at some of the dinosaurs here.
> http://www.oldradio.com/archives/hardware/TV/RCA-TV.htm
Thames TV (the makers of Benny Hill) replaced their venerable EMI 2001
with TK 47 at their Teddington studios. Not much liked by the camera
operators as their larger size made some studio shots impossible.
--
*Don't byte off more than you can view *
isw
"Dave Plowman (News)" <da...@davenoise.co.uk> wrote:
> In article <isw-D8D39A.22002707042010@[216.168.3.50]>,
> isw <i...@witzend.com> wrote:
> > In article <hpibre$pjs$1...@news.eternal-september.org>,
> > "William Sommerwerck" <grizzle...@comcast.net> wrote:
>
> > > > Registration on cameras. Convergence on monitors?
> > >
> > > Yes. Thanks for the correction.
> > >
> > >
> > > > Did you have videcon colour cameras? First UK ones
> > > > were Plumbicon.
> > >
> > > Yes, because you started so late.
> > >
> > > The first RCA cameras used vidicons (I think) -- though they might
> > > have used image orhticons.
>
> > Iconoscope first, then orthicon, then image orthicon. Vidicons were
> > first used for film chains, and later as the color (as opposed to
> > luminance) pickups in *some* cameras.
>
> Are you saying there were iconoscope colour cameras actually in use?
Of course not. I was responding to "The first RCA cameras used vidicons"
-- nothing about color.
But now I think about it, I suppose it's possible that some of the early
CBS field-sequential color work was done with iconoscopes -- or even
image dissectors...
Isaac