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What was the largest 4:3 monitor, period?

lowen said:
VHS and Beta both have the same resolution as NTSC broadcast video in terms of number of lines and frame/field rate. 60Hz fields, 262 lines each field, interlaced to 525 lines at 30 Hz frames. (The PAL and SECAM variant has better resolution to in terms of number of lines).

Beta has better resolution in terms of pixels per line than VHS due to differences in the frequency modulation characteristics for the luminance signal as well as a different choice for the color-under chroma signal.

From the Wikipedia article, which has a really nice summary:
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No VHS is not the same resolution, even S-VHS falls short (400 horizontal lines compared to 230).
 
Unknown_K said:
While I still have maybe a dozen CRTs here, they are just for gaming, text is much better on an LCD.
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That is why LCDs took over so quickly. Most PC use was still office based, black on white screens. LCDs lend themselves to this kind of text, even with slow refresh and poor contrast... And as they got cheaper, they were tolerable for playing games, but then demand increased and CRTs began to disappear and the market response was some very good LCDs, LEDs and even Plasma.
 
andy said:
There was a common issue with Sony's later Trinitron monitors that would result in and excessively bright picture with retrace lines. The cause was that the G2 voltage was set too high. I'm not sure if it was drift in the circuit, or something inside the CRT, but reducing the G2 would fix it. Earlier models required you to use special calibration software software. It was also possible to modify the circuit to reduce the G2.

Many later models had a "color restore", or "color return"feature in the menu that would run a built in self calibration. Often that would immediately fix the issue. Some earlier models don't seem to have enough adjustment range, and it didn't help. Note that you have to wait about 10-20 minutes for it to warm up before it will let you do it.
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Yeah, wouldn't begin to know what to do about this.

The monitor has a worse problem now, when I took it apart, I started testing dodgy looking capacitors. A bunch of them were bad or open circuit. I replaced them and tried turning the monitor on, the monitor would turn on and work for about 5 seconds, then quickly ramp up to a blown out full white image and shut off with an amber blinking error code.

I wish television repair shops were still a thing, I'd pay to have this monitor repaired because the tube is still good.
 
Unknown_K said:
No VHS is not the same resolution, even S-VHS falls short (400 horizontal lines compared to 230).
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As with many things, video resolution is more complicated that it would seem. All home video tape formats (apart from a few very early odballs) record the full 525 scan lines. They have to if they are going to be compatible with a TV that expects 525 lines interlaced. Even those odball formats that only recorded one field had to play each filed back twice to be compatible with a normal TV. What varies with formats is the bandwidth of the video signal. When they say "250 lines of resolution", they mean that the bandwidth can resolve an image composed of 250 black and white vertical bars. It confuses many people that you measure "horizontal resolution" by looking at an image of vertical lines. Also, that 250 lines of resolution fits within a width that is equal to the height of the image, not the full picture width. That last detail is important if you're comparing it to digital video formats that are specified by pixel resolution of the full image.

Even lowly VHS has a vertical resolution of 525 lines. The horizontal resolution is about 230, which is much less than broadcast.

At 400 lines, S-VHS is higher resolution than broadcast, which is only about 330, but it's still not "broadcast quality". The signal to noise ratio isn't great, and the chroma resolution is abysmal.
 
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The way it was described to me once is a CRT image is a long scribble on a piece of paper then just folded up hundreds of times. If you took all the scan lines of a single frame and lined them up end to end, there is no "resolution" other than the switching time of the R, G, and B guns in response to variances in the smooth, analog wave going into them. The only two points of control from the deflection hardware perspective are the H and V square pulses being sent alongside this otherwise very analog wave. Each time a V pulse hits, the beam is told to return to the top. Every time the H pulse hits, the beam is told to return to the left.

The end result is that horizontal resolution as defined as the number of distinct voltage variations applied to the guns from one H pulse to the next is completely arbitrary, all that matters to the thing sending it is that whatever the left side of that arbitrary analog wave is, it has to be hitting the guns when the H pulse has finished dragging the beam back to the left, and whatever is expected to display must be complete when that beam gets to the other side.

Not to overexplain raster display to those in the know, but the "undefined" horizontal resolution of analog video formats in general has interested me for a long time, especially WRT to how could the same phenomenon (not to mention arbitrary number and thickness of scanlines) be achieved aside from CRT-based display technology that doesn't result in the kind of interpolation seen in displays based on a strict grid in the H/V directions.
 
cj7hawk said:
Sony trinitrons also had color issues in Australia - At the time, we were told that it was because they were calibrated for the Northern Hemisphere....
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Yeah, that's actually just our nice way of saying, "Not rated to withstand use by Aussies." :-)

Unknown_K said:
The first desktop LCD monitors were expensive shit, no idea how people spent that kind of money for bad color and ghosting....
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As well as the "text works ok on those" thing someone else pointed out, it's also worth remembering that to some people the significantly smaller size over a CRT is quite valuable. Many people in Japanese offices have a desk that's only 100 cm × 60 cm, and a 14" CRT takes up a substantial chunk of that.

Unknown_K said:
No VHS is not the same resolution, even S-VHS falls short (400 horizontal lines compared to 230).
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The terminology on Wikipedia (and many other sources) is confusing. It gets it right at one point saying that "VHS horizontal resolution is 240 TVL," (and linking to the key term its using); when it later says, "Super VHS...extended the bandwidth to over 5 megahertz, yielding 420 analog horizontal" it means 420 TVL. This is a measure of horizontal resolution within a single scan line, and has nothing to do with the number of scan lines on the screen. Andy helps clarify this as well, though rather than saying,
andy said:
At 400 lines, S-VHS is higher resolution than broadcast, which is only about 330...
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I feel he'd be more clear to say "at 400 TVL," just so he's precise about which "lines" (horizontal bandwidth or the number of lines vertically up and down the screen) he's measuring.

andy said:
...but it's still not "broadcast quality". The signal to noise ratio isn't great, and the chroma resolution is abysmal.
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That's a very important point: when you introduce colour, and your signal isn't separate RGB, the colour resolution is usually different from the black-and-white resolution, and simply having colour available in the signal (even if all the images are black and white) can reduce the overall horizontal resolution. (Thus all the wonderful "colour artifacting" stuff, where a sequence of vertical lines suddenly turns into a flat plane of a single colour.)

segaloco said:
...not to mention arbitrary number and thickness of scanlines....
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That's not arbitrary in most systems I've seen. Certainly in NTSC it's fixed (although any individual display may have a greater or lesser thickness the scan lines it generates). If you're talking about the "scanlines" that retro-gamers refer to, that's actually just due to only half the scan lines being drawn on most old computers and consoles (they draw 0, 2, 4, 6 every field instead of drawing 1,3,5 on alternating fields).

segaloco said:
) be achieved aside from CRT-based display technology that doesn't result in the kind of interpolation seen in displays based on a strict grid in the H/V directions.
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Even CRTs can introduce grids in the horizontal direction. On NTSC black and white CRTs a scan line is truly analogue series of intensity values, but on colour CRTs you of course have the shadow mask or aperture grille dividing that line up into dots.

If you're interested in pursuing the details a bit, I have some personal notes on video that may or may not be helpful. They're rather terse, but there are a number of good references there that take more time to explain things than my summary.
 
cjs said:
That's not arbitrary in most systems I've seen. Certainly in NTSC it's fixed (although any individual display may have a greater or lesser thickness the scan lines it generates). If you're talking about the "scanlines" that retro-gamers refer to, that's actually just due to only half the scan lines being drawn on most old computers and consoles (they draw 0, 2, 4, 6 every field instead of drawing 1,3,5 on alternating fields).
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I'm mostly referring to the technology in theory rather than practice. Production systems of course settled on their various standards, but it's more the difference in limitations of what could be done with a given technology. Mess with the focus of a TV beam enough and that thing'll get thick but soft and feathery, I find it all entrancing even knowing how it all works.

As far as grids, yeah you have the pitch of the mask that provides its own weird concept of a horizontal resolution, but the way everything interpolates to fit the clocks idea of that line and the mask's idea of those phosphors is much more inspiring than the same being applied to LCD pixels. I don't know much about plasma other than that they're heavy, phosphor based, and get hot. Never had one myself, had one once in a motel room for a week and just remember how hot it got. My wonder is if the general idea of phosphor screens could've still been improved on in some sort of way...but plasmas were the last phosphors as far as I'm aware outside of laboratory settings.
 
I only kept one CRT but I am glad I did.

I often which large aquare monitors were still a thing, though.
 
cjs said:
Yeah, that's actually just our nice way of saying, "Not rated to withstand use by Aussies." :-)
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A reasonable thought - Japanese engineering is up there with the best is the world and can handle motorcycles being driven at boom gates at unreasonable speeds, but it's still a long way off of being able to deal with Australians or Australian products.

That's why it's safer to buy lower grade fuel for Japanese reactors from the US - they just can't handle the Australian stuff. Too strong.
ref: https://www.sbs.com.au/language/jap...d-to-the-fukushima-nuclear-accident/8ytdbud1z

If you feed your engineers Vegemite, they will become giants amongst men and be able to handle whatever the world ( and Australia ) can throw at them. Let me know if you want me to send you a jar - :)

 
cj7hawk said:
If you feed your engineers Vegemite, they will become giants amongst men and be able to handle whatever the world ( and Australia ) can throw at them. Let me know if you want me to send you a jar - :)
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I will pass, thank-you, and just hope that XXXX will do a good enough job at that. :-)
 
Well that's interesting. I'd bet money I could get it to work on a normal PC.

Edit: that being said, everything on the linked site looks like 16:9.
 
hunterjwizzard said:
Well that's interesting. I'd bet money I could get it to work on a normal PC.

Edit: that being said, everything on the linked site looks like 16:9.
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Nah, old medical imagers are locked to 4:3 at that resolution, the specific 4:3 models in question are WIDE CX30 and CX50 (5:4 2560x2048).
Others have gotten them as salvage/used, they don’t have much in the way of non-proprietary video inputs (like 1 DisplayPort) and they require proprietary software to adjust the image so you get whatever the screen does which is usually pretty good considering the pro spec.

There was a Samsung 23” 4:3 LCD also so there is hope someone will grab the masks at some point.
 
It looks to achieve 4:3 by turning a 16:9 panel sideways and then using only a portion of the screen.

I'm not suggesting there's anything at all wrong with this. In fact if I can ever get my hands on one of these I am absolutely down to try it.

But it does seem like the same effect could be achieved on an ordinary 16:9 monitor.
 
Portrait: 378 x 535.9 x 248.8 Landscape: 506.2 x 471.8 x 248.8

The dimensions look more 1:1, the image is likely an optical illusion
 
I have a video card used for medical imaging and kind of wonder how nice those LCD monitors are that go with it.
 
Of course if anyone actually gets their hands on a medical imaging machine the very first thing you have to do is install DOOM.
 
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