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PostPosted: Thu Feb 01, 2018 3:15 am 
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That said, you could make a filter that comes very close to looking like what one particular CRT could look like, especially with the monitor resolutions that are available today.

And I think there are actually already some very good ones out there.

But at least we can all agree that just drawing a black line every second line isn't the way to go. :P


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PostPosted: Thu Feb 01, 2018 7:21 am 
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Sumez wrote:
That said, you could make a filter that comes very close to looking like what one particular CRT could look like, especially with the monitor resolutions that are available today.

So basically you're saying that 4k resolution finally have an usage other than pure commercial?


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PostPosted: Thu Feb 01, 2018 8:02 am 
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Even a 720p TV should be able to give a passable simulation of beam spreading at 3x zoom.


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PostPosted: Thu Feb 01, 2018 1:04 pm 
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I think emulated scan lines look way too dark. If a CRT has dark spaces between lines, the lines are usually bright enough to compensate for it. On an LCD you can't have black and white stripes and still make it look white.


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PostPosted: Thu Feb 01, 2018 1:24 pm 
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psycopathicteen wrote:
If a CRT has dark spaces between lines, the lines are usually bright enough to compensate for it. On an LCD you can't have black and white stripes and still make it look white.

Yes, this is a very important aspect of it. If the beam isn't interlacing it is concentrating twice as much light on half the space (i.e. no change in overall intensity vs. interlaced mode). There is no equivalent range of intensity on an LCD with emulated scanlines. Plus CRTs are brighter than LCDs just as a baseline factor, even before taking into account scanlines.


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PostPosted: Thu Feb 01, 2018 3:23 pm 
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rainwarrior wrote:
psycopathicteen wrote:
If a CRT has dark spaces between lines, the lines are usually bright enough to compensate for it. On an LCD you can't have black and white stripes and still make it look white.

Yes, this is a very important aspect of it. If the beam isn't interlacing it is concentrating twice as much light on half the space (i.e. no change in overall intensity vs. interlaced mode). There is no equivalent range of intensity on an LCD with emulated scanlines. Plus CRTs are brighter than LCDs just as a baseline factor, even before taking into account scanlines.


The "solution" is to just have a cranked up LCD backlight, but that's kind of janky. No matter how you look at it, emulating scanlines sacrifices total luminosity.

To say CRTs are brighter than LCDs is a bit of an umbrella statement that's untrue in a lot of cases, but your average CRT TV / 15Khz monitor in good shape will be very bright. A PC CRT is often quite a bit dimmer.

For what it's worth, this is what a nearly NOS 32" tube looks like - and it's not a PVM, or other fancy broadcast video monitor. Just a big honking slot mask curved tube.

Image

(Using a game I expect most people here to recogniz!)


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PostPosted: Fri Feb 02, 2018 1:14 am 
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mikejmoffitt wrote:
The "solution" is to just have a cranked up LCD backlight, but that's kind of janky. No matter how you look at it, emulating scanlines sacrifices total luminosity.

To say CRTs are brighter than LCDs is a bit of an umbrella statement that's untrue in a lot of cases, but your average CRT TV / 15Khz monitor in good shape will be very bright. A PC CRT is often quite a bit dimmer.

Yeah, I was overstating it a little but I did mean in general, and I was a little bit conflating with contrast, i.e. turning up the backlight will also noticably raise the black level. ...but some LCDs are better than others, of course, and the technology has improved over the years.


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PostPosted: Wed Feb 14, 2018 8:07 am 
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Take a look at this zoom up of a Pac-Man CRT.

Image

It appears to have horizontal scanlines. But, if you look closely, that effect is actually a consequence of the delta-gun shadow mask and phosphor dot layout. In fact, the monitor is rotated 90 degrees; the electron gun is actually sweeping vertically. I bring this up to point out that "scanlines" are not just the result of highly focused beams.


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PostPosted: Wed Feb 14, 2018 11:41 am 
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Scanlines are literally the result of focused beams. Those horizontal lines are as you mentioned just a result of the phosphor layout, and aren't scanlines.


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PostPosted: Wed Feb 14, 2018 12:15 pm 
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Sure, but his point is that the phosphor layout is also a visible artifact, and the individual phosphor elements are often large enough to be important to the correct emulation of scanlines.

I mean, not on a Trinitron tube (or my TV). But for anything with the more conventional triangular electron gun arrangement...


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PostPosted: Thu Feb 15, 2018 12:37 am 
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I never actually considered that detail, so it's cool to have pointed out.

What a horrible monitor in that image, though :D I don't think I've ever seen Pac-Man looking that blurry.


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PostPosted: Fri Feb 16, 2018 7:52 am 
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Here are a few more Pac-Man pics:

https://i.imgur.com/mC1VCf8.jpg
https://i.imgur.com/qBhnD3z.jpg
https://i.imgur.com/75VOAMw.jpg
https://i.imgur.com/nHumYlc.jpg
https://i.imgur.com/ST5974d.jpg
https://i.imgur.com/Q9UBSCU.jpg
https://i.imgur.com/mDcgJw8.jpg

Apparently, it's an in-line color mask, not delta format. The pic posted earlier in this thread was apparently too blurry. Though, I have seen machines where the pseudo-horizontal-scanlines were highly pronounced with clear gaps between the rows.

Also, I always wondered why a brick pattern is used as opposed to what you see in Trinitron monitors. Was it due to technological limitations or was it an attempt to reduce visible scanlines?


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