Auto TV Picture Adjustment - VIR In the Digital Age?

step and multiburst.

t 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 bar s the same, or at a specified differential level. And there were settings f o it, it is just they were referenced to those levels.

dth problems, maybe even multipath using the stairstep and/or the mutiburst . But again, there was no money in it.

The thing is it was adjusted to that test signal. The video is the video, i f it looks s***ty it is not our fault, that is how it is. Our equipment is fine.

as young we only had a few TV stations. I mean some people had UHF converto rs. 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.

They actually DID do bandwidth correction with Ghost Cancelling Reference ( GCR) which was one line of continuous sweep from 100 KHz to 4.2MHz Any freq uency response variation between the insertion point and recovery point was corrected. Keep in mind that multipath (ghosts) manifest as response devia tions. We had bad ghost on KCBS 2 in LA from antenna feed and the GCR box c leaned nearly all of it up. The surprise came on KCET 28 which had no ghost s at all but when the box locked up the detail 'popped' - that dramatically .

I don't know if home TVs looked at VITS bars as the line number was not fix ed and decoding a line of bars is sort of silly. The VIR was specifically d esigned for this task as the subcarrier (in the line, not the burst) was a defined phase and amplitude on a fixed level pedestal to set luma gain.

Gotta tell ya though, I do not miss analog TV and all of its myriad flaws a nd limitations with illegal colors and video levels. AND, aligning a low ba nd VHF transmitter for response, Incidental Carrier Phase Modulation, delay and efficiency was tedious getting the 3 or 4 linear amplifiers that follo wed the exciter all behaving properly.

Short answer: "Yup".

Long answer: Significant experience with NTSC and participation in the development of MPEG and HDTV.

Isaac

Google "Eidophor".

Isaac

Again isw/Isaac:

We're talking about the sets themselves, not NTSC or ATSC transmissions. Those have 6500K as the grayscale and D65 as the illuminant. If you see a lot of blue from those marks then something is wrong with what you are viewing them ON.

Most current Consumer TVs out of box are NOT set for accurate viewing by either standard. A lot of them may have an accurate preset(Movie or THX), but are not set to that at the factory.

They are put in the bluest, brightest, over- saturated, oversharpened mode possible, with a bunch of edge enhancers and "noise reducers" enabled, and most consumers don't even bother to look for a menu where they can change that.

And trying to explain that to them, as it has been trying to explain to some on here, is akin to explaining it to a lamp post. It seems that I must be the ONLY usenet participant on either sci.electronics.repair, rec.video, or alt.video who gives a crap about display accuracy and calibration, because no one else cares to bring it up.

JOE KANE where are you when we need you????

snipped-for-privacy@gmail.com skrev:

You still don't get it.

You want to replace the factory presets with your own presets.

You can not get a more correct image without looking/measuring the resulting output, as an absolute value of 50% red 50% green 50% blue might have different result on different makes and models of screens.

You cannot calibrate without looking at the screen. It cannot be done remotely.

Leif

Early color TV did not work that way. Monochrome cameras were set up to pic kup that as well as possible, and that was something like 72 % green, and w hatever was left, mainly to the red but about a third of it to the blue. So mething like that. In fact there are a few different colorimetries.

They were never equal simply because the way the human eye works and now, t hat is not going to get better. Like someone said, doens't anyone care abou t the accuracy ?

Well the fact is, I don't. Not that much. I am happy with a 1990s TV, CRT t ype. Standard def. I don't mind seeing the scan lines. The HDTV is nice, bu t I simply do not need it for three hours of viewing a month or whatever it is. If I get a hnakerin to watch the tube I will go to that, ummm, yeeah H ULU and go see my old buddy Matt Dillon. and his buddy Doc.

Know one time Doc told this guy if he saw him beat his pregnant Wife again he would kill him ? Subsequently he caught the MF at it and then shot him. Some other guy, I think Newly who was one of the deputies said "you killed him" and Doc replied "I meant to".

Now that I like. Not ghosts, goblins and all that bullshit.

And the other thing is that when we had three TV stations, we had to look a t the TV guide to see what to watch. MAKE A CHOICE.

Now we got 300 stations and nothing to watch. When the best thing on is Gor don Ramsay and this is costing you a hundred bucks a fuckoing month, someti ng is wrong.

Bottom line, make the picture as perfect as you want, but of what ?

snipped-for-privacy@gmail.com wrote: "Well the fact is, I don't. Not that much. I am happy with a

So would I be - once I set at least the basic controls properly. Standard or high-def doesn't matter. Getting the grayscale, chroma, dynamic range and peaking right is more important than lines or pixels. Once I saw accurate, I was hooked. Nothing else would satisfy me! :)

Some sets you simply couldn't. They played woith the color demnodulation angle sometims, prety much for flesh correction I thingk sometimes based on the engineering department's refereces.

And then there were those elcheapo NAPs with the phosphor optimized for flourescnt lighting in the stores that were s*it once you got them home.

I put myself thru college in 1953-57 doing Admiral tv repair in Fort Pierce , Florida. There was tremendous variability in how sets came from the fact ory. There was also tremendous variability in what various consumers wante d as the color of "white". We aimed to keep our customers happy and would set "white" to whatever was their preference.

The nearest tv station was in West Palm Beach 50 miles to the south, all ot hers were in Miami, 120 miles to the south. Atmospheric conditions determi ned the quality of the signals received at those distances. The yagi anten nas used had back lobes that would also pick up Jacksonville 200 miles to t he north, on the same channels as Miami, under certain atmospheric conditio ns. The resulting signals gave strange effects.

The white block in the upper left-hand corner of the picture signalling a s witch to a commercial was a holdover from motion pictures. When the reel of film was almost over, like about 10 seconds from the end, the white block was a signal to the projectionist to switch to the alternate projector whic h picked up the "story line" at exactly the end of the film in the first pr ojector. Since early tv used a lot of film-based programming, the white bl ock made the transition to tv in that manner.

hrho.. wrote: "tremendous variability in what various consumers wanted as the color of "white". We aimed to keep our customers happy and would set "white" to whatever was their preference. "

B B B bbble chhhhh!!!! (K-man kneeling before the American Standard vomiting)

How awful! And that word "preferences". There's only accurate - and innacurate!

Might as well. These new shows and movies seem to want to make you think yo ur TV is screwed up. The blacks are green, and I lknow it is not the TV bec ause it isn't there when you turn the color down. And then they blue out th ings. And recently I saw a show in which when they changed certain scenes t hey made it look like you have a horizontal sync problem.

In sound, if you have a properly miked concert and goood speakers, maybe yo u want to leave the tone controls on flat. But synthesized music ? Electric guitars. All highly equalized before it ever gets there.

Accurate to what ?

jurb.. wrote: "Accurate to what?"

I'm not even going to entertain that question. It shows how little folks care about calibration on these supposedly "technical" newsgroups.

Google "display calibration" and "SMPTE" and learn about it. Learn the significance of 6500K color temperature and illuminant D65, and what color bars are for.

It was a purely rhetorical in nature. My point was you don't watch a test signal.

I don't disagree with you. The people who want their greyscale to be a brownscale or a bluescale are like the people who want to turn the bass or treble up or down on music.

Maybe you are the last purist.

I know all about test patterns. Got no use for them without a TV.

jurb wrote: ">jurb.. wrote: "Accurate to what?" I'm not even going to entertain that question. >It shows how little folks care about calibration on these supposedly "technical" >newsgroups. Google "display calibration" and "SMPTE" and learn about it.

It was a purely rhetorical in nature. My point was you don't watch a test signal.

I don't disagree with you. The people who want their greyscale to be a brownscale or a bluescale are like the people who want to turn the bass or treble up or down on music."

The patterns are designed to result in accurate viewing of actual material!

Even if ten people strived for correct skin tone by eye, you'd still get ten different results, all else being equal.

Patterns are standardized. Can't eff up the settings with them!

So are you ready to take a calibrrated light box and transparency for campare ?

That is really the only way to do it.

snipped-for-privacy@sbcglobal.net kom med denne ide:

A question linked to a random message in this thread:

Are the colours in Miami as vivid as in the series CSI-Miami?

Leif

Leif Neland:

Of course not. The colors in CSI Miami were produced that way. Same as the green overtones in "The Matrix".

Think of calibration as an alignment process. After such, the TV will produce colors exactly as the producers of movies and TV shows intended them to be viewed. Content that is not overly produced, and reflects reality, such as the news, will pass through accordingly.

The content itself is not a calibration source - the patterns on discs such as Avia, Spear & Munsil, or Digital HD Video Essentials are.

Display calibration is akin to a wheel alignment: It is done in a shop with precision measuring devices & tools. It allows the vehicle to perform ideally on the widest variety of road surfaces. Video calibration is done with industry-established standardized patterns to allow the TV to more accurately display the widest variety of program colors and luminance ranges.

To adjust a TV so that CSI Miami colors appear more life-like is like aligning a car to perform best on the 33degree bank turns at Talladega Speedway. It will not track true at other venues or environments.

The 'Cue mark' was the upper right, and in a series of three. They were made by either scraping away the emulsion, or punching a pinhole for several frames for each cue mark.

The first to alert the operator. The second was to start the other projector, and the third to switch the semaphores to switch the optical path from one projector to the other. I ran a pair of RCA TP66, 16 mm film projectors at an AFRTS TV station, for a year, back in the '70s.

I got myself through college in the early sixties by working in a local TV station's engineering department. Back then, there was no other way to distribute movies for things like the local "late movie" than as 16mm film on large reels. The movies were always provided as packages of a couple dozen (generally one or two decent ones and the rest dogs). The cans of film worked their way around, one movie at the time, through a series of local stations -- you got them from KXXX-TV and sent them on to KYYY-TV, who then sent them on, etc. Assuming the station(s) upstream of you were responsible, you got a "new" movie every week.

By the time the film rolls had been around that circuit once or twice, nearly every frame in the whole film had been punctured with a cue mark (because every station had their own idea of where the commercials should be inserted).

All the holes were, of course, bright white, which messed with the automatic video gain circuitry of the projectors.

Isaac