Auto TV Picture Adjustment - VIR In the Digital Age?

[Leif Neland]

jurb6006@gmail.com forklarede den 28-04-2015:

That was a white rectangle at the upper left of the frame, so far up in the
corner that no TV of the time would show it due to overscan and/or not a
quite rectangular screen. It was only on network programming, obviously that
tells the local stations to cue their local commercials which would be
interspersed with the national commercials. I am pretty sure those
(imperfect) commercial "zappers" used that signal.

Here, there is station logo when the "real" program is send, the
station logo is turned off during commercials.

I really wish my PVR could use this for pausing recording or for
skipping during playback.

Leif

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Eller begge.

 

[Michael Black]

On Mon, 27 Apr 2015, jurb6006@gmail.com wrote:

"That VIR system was more of a gimmick to me,..."

Not really a gimmick. It did work but only adjusted the chroma level and phase. (color and tint) It could have done more, like keep the gain and pedestal (contrast and brightness) right, now that sets had DC restoration. They decided not to do that and I think I understand why. Nowhere in the world did people adjust their TVs like here. Some had the color too high. Alot of them, and I mean quite alot of them had the faces too red with the tint (or hue) control. Those people would say I set the faces too green.

Over in Europe, with a slightly more modern system there was no hue or tint control. The phase errors in NTSC were caused by vulnerability to frequency response errors and a few other things to which PAL for example was immune.

The VIR or VITS (slightly different but very similar) was not intended to set the color on people's TV sets. It was intended for the stations to use. In NYC there was a control room for the major network, let's say NBC. They originated the shows on the network, like the national news and other nationwide programming. The loop went all the way around the country and it was of course degraded by the time it got back. And delayed of course.

But the VITS or VIR was hat told them alot more about the signal quality. It had one line of NTSC color bars, one line of staristep and one line of multiburst. (later, closed captioing was right under it) They could have used the stairstep for ghost cancellation I think but never did. The technology was not cheap enough for consumers. Phillips DID develop a ghost cancelling system and I think the stations did start =sending its specified signal during vertical retrace, but I never saw it in operation and have doubts as to whether even one single unit was sold. But Phillips built TVs had a video in/out loop for it just like a tape monitor on an audio amp. (for a few years only)

On a scope with dual time base you could separate those lines out from
the vertical retrace interval and see the actual waveforms. When TVs had
a vertical hold control you could roll it down and have a look. Another
cool thing that was in there was a signal for the commercials to start.

That was a white rectangle at the upper left of the frame, so far up in
the corner that no TV of the time would show it due to overscan and/or
not a quite rectangular screen. It was only on network programming,
obviously that tells the local stations to cue their local commercials
which would be interspersed with the national commercials. I am pretty
sure those (imperfect) commercial "zappers" used that signal.

I was using a Commodore monitor with a VCR as a tv set in the until I got
an LCD DTV set in 2011. And one of the Commodore monitors I used
displayed that white block very cleanly. I didn't know about it, but soon
realized it was an indicator of a commercial, really useful. But I think
I only noticed it on one station, or maybe "not all stations". And then I
had to change the monitor to another Commodore, and it no longer showed
that corner with the white block.

Michael

 

Just for kicks, I did a search for "calibration" on the
newsgroup rec.video. Now answer me this:

WHY hasn't the subject of display calibration been
brought up since the year 2000?!

 

[Bruce Esquibel]

thekmanrocks@gmail.com wrote:

Just for kicks, I did a search for "calibration" on the
newsgroup rec.video. Now answer me this:

WHY hasn't the subject of display calibration been
brought up since the year 2000?!

Hmmm, because that is about the time CRT's started to get phased out?

I mean I know anything today can be tweaked to be "a bit better" but it's
not going to be anything as dramatic as the CRT days.

What was the name of that group, SFS or FSS something, they had like classes
to do complete calibration on projectors, tv's and other display devices
back in the 1990's. Seemed to fade away about the same time from being
relevant. I seen them mentioned recently, guess they are still plugging away
with front projection systems.

This thread is getting silly anyway, people seem to be in search of an
answer to a problem that doesn't really matter anymore. I can see
differences in technologies, plasma vs. lcd vs. led vs. oled but within each
family, not so much to matter, to me anyways.

-bruce
bje@ripco.com

 

Bruce Esquibel:

The name of the group, in my reply just
before yours, is REC.VIDEO.


The problem still exists today, just from
a different end: The consumer's display.


Due to consumers either not knowing or
just not caring, their modern digital/HD
TVs are left in, ironically, the WORST
modes ever contrived for a TV in the
history of television. This may be called
'Vivid' or 'Dynamic', by different manu-
facturers.


And many set owners don't even know,
or care, that that a menu even EXISTS
for them to get a more accurate picture
by just turning off a few things, and
adjusting a few others. Plus, their TV
will consume less energy and last much
longer.


But all that doesn't matter, Bruce, does it?
Nor does the fact that an Imaging Science
Foundation exists, along with standards
set long ago by both them and the SMPTE.


They must just be out of their mind, stark-
raving CUCKOO for all some of us care.

 

On Tuesday, April 28, 2015 at 1:03:40 PM UTC-7, thekma...@gmail.com wrote:

Leif: Read the article again: https://books.google.com/books?id=CgEAAAAAMBAJ&pg=PA109&lpg=PA109&dq=%22vertical+interval+reference%22&source=bl&ots=FS5yReiiMN&sig=Z-BKLSSQvDNzuT0WlmUEp0LHEqk&hl=en&sa=X&ei=lsU8VbfELciagwT2qYDYAg&ved=0CEUQ6AEwDA#v=onepage&q=%22vertical%20interval%20reference%22&f=true


You're not getting what VIR *also* did.

It also internally adjusted the picture controls to
proper levels, regardless of how the kid screwed
up the knobs on dad's new 25" console.

That's all well and good but VIR applied to analog TV broadcasting which was turned off - permanently (YEA) - in June 2009. VIR had a preset amplitude and phase (hue) subcarrier riding on a defined amplitude pedestal to set brightness, contrast hue and saturation and nothing more. Keep in mind that this does NOTHING about bias and gain on the display (back then CRT) device.. How your TV was aligned was up to you and your repair tech.

That's ALL that VIR could and did do.

G˛

 

[John-Del]

On Tuesday, May 5, 2015 at 5:39:42 PM UTC-4, stra...@yahoo.com wrote:
>> VIR had a preset amplitude and phase (hue) subcarrier riding on a defined amplitude pedestal

It was a bit more than that. It wasn't a preset value; the broadcaster would set the saturation and phase, even changing it to compensate for different film systems or video tape variances from program to program.


>>>....riding on a defined amplitude pedestal to set brightness, contrast hue and saturation and nothing more.

My recollection is that it did not adjust brightness or picture (contrast)

>>>>Keep in mind that this does NOTHING about bias and gain on the display (back then CRT) device. How your TV was aligned was up to you and your repair tech.

That's true, but grey scale and black level were amazingly close from sample to sample. I would say that the grey scale adjustment of the average GE from that era was quite close to perfect. The Japanese TVs of that era were shipped above 9000 k.

 

6:53 PMJohn-Del wrote:
"That's true, but grey scale and black level were amazingly close from sample to sample.
I would say that the grey scale adjustment of the average GE from that era was quite close to
perfect. The Japanese TVs of that era were shipped above 9000 k. "


Were sets really that close to accurate(6500) 30-40 years ago? And does that suggest
that the trend toward bluer-brighter-oversharpened TVs is relatively new - post-millennium?


If that was so, then my notion that calibration and accurate adjustment matter more than
number of lines or pixels is right on. And I wish I had one of those old knob-clicker-tuners
sitting around the house - perhaps underneath my LED smart TV as a base for it!


Of course, calibration is a taboo subject on these newsgroups, despite the factory settings
of modern flat screens meaning that calibration is needed NOW more than ever in the history
of television!

 

See? Soon as I mention the "c-" word everyone runs under a table
nearby or folds up like a two-dollar suitcase.

 

On Tuesday, May 5, 2015 at 3:53:28 PM UTC-7, John-Del wrote:

On Tuesday, May 5, 2015 at 5:39:42 PM UTC-4, stra...@yahoo.com wrote:
VIR had a preset amplitude and phase (hue) subcarrier riding on a defined amplitude pedestal

It was a bit more than that. It wasn't a preset value; the broadcaster would set the saturation and phase, even changing it to compensate for different film systems or video tape variances from program to program.


....riding on a defined amplitude pedestal to set brightness, contrast hue and saturation and nothing more.

My recollection is that it did not adjust brightness or picture (contrast)

Keep in mind that this does NOTHING about bias and gain on the display (back then CRT) device. How your TV was aligned was up to you and your repair tech.

That's true, but grey scale and black level were amazingly close from sample to sample. I would say that the grey scale adjustment of the average GE from that era was quite close to perfect. The Japanese TVs of that era were shipped above 9000 k.

From Wikipedia. I know this is correct because I used to maintain this equipment at the CBS affiliate in Madison WI, WISC TV 3.

VIR (or Vertical interval reference), widely adopted in the 1980s, attempts to correct some of the color problems with NTSC video by adding studio-inserted reference data for luminance and chrominance levels on line 19.[25] Suitably equipped television sets could then employ these data in order to adjust the display to a closer match of the original studio image. The actual VIR signal contains three sections, the first having 70 percent luminance and the same chrominance as the color burst signal, and the other two having 50 percent and 7.5 percent luminance respectively.[26]

The signal was NOT altered by the local broadcaster. It was intended to correct black level, gain, phase (hue) and saturation errors that may occur during transmission. In Channel 3s case, a Tektronix 1440 (?) video corrector processed the incoming CBS network feed to maintain those parameters. At the time network came via terrestrial microwave and was extremely consistent even without the corrector.

IF your TV referenced VIR, all it did was those 4 parameters. Any bias (black level) and gain adjustments AFTER the VIR processing may or may not be calibrated correctly. What it DID ensure was that it would be consistent. That's all.

G˛

 

[isw]

In article <8f6a4d92-e907-407f-bca0-949d267f9f45@googlegroups.com>,
thekmanrocks@gmail.com wrote:

6:53 PMJohn-Del wrote:
"That's true, but grey scale and black level were amazingly close from sample
to sample.
I would say that the grey scale adjustment of the average GE from that era
was quite close to
perfect. The Japanese TVs of that era were shipped above 9000 k. "


Were sets really that close to accurate(6500) 30-40 years ago? And does that
suggest
that the trend toward bluer-brighter-oversharpened TVs is relatively new -
post-millennium?

Bluer, or just closer to white than you're used to?

Isaac

 

isw wrote:

"Bluer, or just closer to white than you're used to?

Isaac"


Closer to white than I'm used to? White is not
supposed to be bluish. Today's TVs ship to retailers
with the color temp closer to that Japanese standard
mentioned a couple replies back(9,000K), which
renders material produced at 5400(old B&W movies)
or 6,500K(broadcast) most inaccurately - bluish.


Question: Have you seen an accurate or calibrated
accurate TV? Or one with at least the Basic-Five
controls set correctly with medium or warm color
temp setting?

 

Chuck: "oil based projection tv"


????

 

Chuck:

Some kind of lubricant..

I know what oil-based paintings are, but
oil-based TV? That one through me, lol!

 

[John-Del]

On Wednesday, May 6, 2015 at 11:00:27 AM UTC-4, thekma...@gmail.com wrote:

I know what oil-based paintings are, but
oil-based TV?

Refresh rate must have sucked.... [rimshot]


Well, it's not April 1st so I looked and:

http://www.earlytelevision.org/eidophor.html

 

[John-Del]

On Tuesday, May 5, 2015 at 7:35:27 PM UTC-4, thekma...@gmail.com wrote:

Were sets really that close to accurate(6500) 30-40 years ago? And does that suggest
that the trend toward bluer-brighter-oversharpened TVs is relatively new - post-millennium?

In the tube era, TVs came out of the box a mess. I was just a kid but learned to converge and grey scale RCAs and Zeniths (Zeniths were better prepped out of the box) in a hurry before delivery. Delta tube convergence was hit or miss, but RCA's adjustments had less interaction than anyone.

Once the solid state XL-100 hit the market in 1971, things changed. These came out of the box almost perfect and the Zeniths and GEs showed big improvements as well. The Sonys and Panasonics were consistent, but consistently blue.

RCA always specified 6500 Kelvin for their grey scale.

 

[Chuck]

On Tue, 5 May 2015 15:53:24 -0700 (PDT), John-Del <ohger1s@aol.com>
wrote:

On Tuesday, May 5, 2015 at 5:39:42 PM UTC-4, stra...@yahoo.com wrote:
VIR had a preset amplitude and phase (hue) subcarrier riding on a defined amplitude pedestal

It was a bit more than that. It wasn't a preset value; the broadcaster would set the saturation and phase, even changing it to compensate for different film systems or video tape variances from program to program.


....riding on a defined amplitude pedestal to set brightness, contrast hue and saturation and nothing more.

My recollection is that it did not adjust brightness or picture (contrast)

Keep in mind that this does NOTHING about bias and gain on the display (back then CRT) device. How your TV was aligned was up to you and your repair tech.

That's true, but grey scale and black level were amazingly close from sample to sample. I would say that the grey scale adjustment of the average GE from that era was quite close to perfect. The Japanese TVs of that era were shipped above 9000 k.

You are correct that VIR only set saturation and hue. Those PM
chassis GEs were awesome. It is a shame they abandomed them when they
boughrt RCA. GE was in the process of selling an oil based consumer
projection tv when the division was folded.

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[Chuck]

On Wed, 06 May 2015 08:16:36 -0500, Chuck <chuck@mydeja.net> wrote:

On Tue, 5 May 2015 15:53:24 -0700 (PDT), John-Del <ohger1s@aol.com
wrote:

On Tuesday, May 5, 2015 at 5:39:42 PM UTC-4, stra...@yahoo.com wrote:
VIR had a preset amplitude and phase (hue) subcarrier riding on a defined amplitude pedestal

It was a bit more than that. It wasn't a preset value; the broadcaster would set the saturation and phase, even changing it to compensate for different film systems or video tape variances from program to program.


....riding on a defined amplitude pedestal to set brightness, contrast hue and saturation and nothing more.

My recollection is that it did not adjust brightness or picture (contrast)

Keep in mind that this does NOTHING about bias and gain on the display (back then CRT) device. How your TV was aligned was up to you and your repair tech.

That's true, but grey scale and black level were amazingly close from sample to sample. I would say that the grey scale adjustment of the average GE from that era was quite close to perfect. The Japanese TVs of that era were shipped above 9000 k.


You are correct that VIR only set saturation and hue. Those PM
chassis GEs were awesome. It is a shame they abandomed them when they
boughrt RCA. GE was in the process of selling an oil based consumer
projection tv when the division was folded.

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I shouldn't have said that the VIR signal didn't have a reference for
luminance adjustment. I believe the PM chassis VIR circuitry didn't
use these values.

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[Chuck]

On Wed, 6 May 2015 06:21:37 -0700 (PDT), thekmanrocks@gmail.com wrote:

Chuck: "oil based projection tv"


????

Look up professional 1980s GE projection televisions for closed
circuit events like fights on Google . They were oil emulsion based.
GE put out a sheet of products that were going to be released in the
next year and that set was one of them. The division folded a month
later.

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"I shouldn't have said that the VIR signal didn't have a reference for
luminance adjustment. "

It did. As I said there was a line of the NTSC color baar standard, stairstep and multiburst.

Though the VIR equipped sets only used two bars of the NTSC color bars, it could have done alot more. There was just no money in it. I don't recall exactly how it worked but it only adjusted the phase to make two of the bars the same, or at a specified differential level. And there were settings fo it, it is just they were referenced to those levels.

Rewalistically, had they wanted to they could have compensated for bandwidth problems, maybe even multipath using the stairstep and/or the mutiburst. But again, there was no money in it.

Broadcasters may well have made adjustments manually, it doesn't matter. The thing is it was adjusted to that test signal. The video is the video, if it looks shitty it is not our fault, that is how it is. Our equipment is fine.

the real problem is that this has become much ado about nothing. when I was young we only had a few TV stations. I mean some people had UHF convertors.. On Friday night we had to look at the TV guide that came with the local newspaper and decide what to watch. Choosing from a whopping five channels in the days of the new UHF band.

Now there are 300 channels and the best button is "power off".