Those dark lines on a CRT television aren't "scanlines"

[jlancaster86]

I'm sure this is news to many, but those dark lines we see on a a CRT television when displaying 240p/288p content are not "scanlines". Those lines are dark precicesly because they aren't being scanned by the electron beam! In fact, A 240p image looks the way it does on a CRT because it's only 50% scanlines rather than the 100% of 480i.

I know this will seem pedantic to some, but it is wrong, and it only serves to make the workings of CRTs and video signals even more confusing to newcomers.

With all the recent advancements in MiSTer's CRT simulations, this is a perfect time to start correcting the record and using more accurate terminology in the names of filters. Something like "darklines" or "blacklines" would be sufficient in my opinion, but I'm sure there are plenty of other options too.

For more information on 240p, watch this video.

Thoughts?

[custardo]

You may be technically correct, but if this is the hill you've chosen to die on I wish you the best of luck.

[akeley]

ISomething like "darklines" or "blacklines"

Yeah, I'm sure this will go down real well in 2022 That aside from overall futility of trying to correct something so deeply embedded by now (a bit like term "retro gaming" which is apparently also semantically incorrect).

Besides, it's rather harmless, since everybody knows what the term refers to anyway. IMO much more beneficial would be trying to explain that the heavily exaggerated "thicc scanlines" look is a modern invention since back then nobody had PVMs nor wanted a "window blind" effect in their image. But that's probably as futile as your idea...

[Lightwave]

Even from a semantic point of view I don't think it matters, as when we talk about a "scanline" filter, the effect includes both the "blacklines" AND the scanlines; you can't have one without the other. For example, with adaptive scanlines, we talk about bloom, which is referring to the increased size of lighter parts of the SCANLINE. The effect is emulating the mechanics of scanlines in any case, so it's not wrong to use the term scanlines to refer to it in general, regardless of which part of it you have in mind when doing so.

[dshadoff]

These lines are noticeable because of the way that scanning takes place. It doesn’t matter that they aren’t explicitly drawn; they are still the result of the scanning process…

I won’t participate in debate; I just thought I’d explain the origin and usage of the term.

[callanabrown]

It's true that you're not "adding scanlines", but you are "showing scanlines" by not printing the scanlines that didn't exist originally when you "enable scanlines".

So who cares

[darksakul]

The term scan lines is used too long to change now.
Even commercial games from retail calls the effects scanlines.

[aberu]

https://stancarey.wordpress.com/2010/02 ... u-want-it/

[grizzly]

Yes your right!
But what i have thought for decades is that it´s called "scanlines" not because your adding blacklines, but because your simulating the scanline effect.
Which means your both right and wrong in my opinion.
Your right about the blacklines, and wrong about the whole "procedure"!

[lamarax]

IMO much more beneficial would be trying to explain that the heavily exaggerated "thicc scanlines" look is a modern invention since back then nobody had PVMs nor wanted a "window blind" effect in their image.

This

Best "scanlines" (or "darklines"), are the ones you don't notice!

I've gathered a little collection of my preferred filters' combination which suit my personal "median" experience of what was it to stare at vastly different CRT screens back in the years, during a long period of tech evolution, be it at home with a computer or a console, or out in the arcade:

My Preset stuff.zip

(6.72 KiB) Downloaded 177 times

These -mind you- are particular to my own display, its calibration, range of settings, and quirks.

Don't forget that, just like CRT tech was widely dispersing and kept developing exponentially between the 1960s and the early millennium, so are the current LCD/OLED/AMOLED panels with their differing sub-pixel grids and whatnot. Not everyone and his cat, has the same 4K LG OLED tv to plug his MiSTer to

[daveo]

I think you’re getting the implementation confused with the result.

It’s a ‘scanline effect’, that yeah you can describe as being implemented on an lcd by effectively adding black lines to the image, but it’s more useful to describe by the result of emulating scanlines.

It’s like if you had a ‘blue tint’ effect. It’s more useful to call it that than describe it as a ‘subtract green and red effect’.

[ToothbrushThreepwood]

If we’re playing devil’s advocate here, I’ll add that if scanline-free monitors had been introduced to us back in 1985, we would all have been hyped up about how we could finally enjoy crisp images without having to ignore the forced horizontal bars splitting the pixels apart.

[C-R-T]

Where did the term come from anyway? First time I even heard about it was in emulators in the late 90s. When CRTs were the only thing we had! Enabling it made the picture look really artificial and weird - those black lines are totally unnatural, most TVs or computer monitors never even had any “scan lines”.

[caad]

The term comes from the technology itself. The electron beam scans across the screen, line by line.

[grizzly]

Scanlines come from the fact that on ALL CRT tubes in tv/monitors it is a electron beam that is scanned across the tube to light up the fosfor on the inside of the tube for a picture.
Thats why jlancaster is partly right in that he black lines is not scanned by the beam and should technically not be named scanlines.

[amstan]

You may be technically correct, but if this is the hill you've chosen to die on I wish you the best of luck.

The black things on a zebra aren't stripes, they're just the absence of white stripes.

[Chris23235]

Where did the term come from anyway? First time I even heard about it was in emulators in the late 90s. When CRTs were the only thing we had! Enabling it made the picture look really artificial and weird - those black lines are totally unnatural, most TVs or computer monitors never even had any “scan lines”.

Scanline options on computer emulators back in the 90s were rather simple but effective. The point was that on a emulators on VGA monitors had resolutions like 800*600 or 1024*768, much higher than the hardware that was emulated. By using scanline filters it was possible to get closer to the resolution of the emulated system.

Additionally many arcade games back in the late 80s had huge CRT Displays running the games in very bright colours (e.g. Outrun, Afterburner). On these displays the non scanned lines were extremely visible and were part of the overall presentation. Take Sega's Super Scaler hardware for example, the games ran in 320*224 on huge monitors if you run these games in 1024*768 without any scanline effect, the graphics won't look like in the arcades at all.

[Malor]

Scanlines come from the fact that on ALL CRT tubes in tv/monitors it is a electron beam that is scanned across the tube to light up the fosfor on the inside of the tube for a picture.
Thats why jlancaster is partly right in that he black lines is not scanned by the beam and should technically not be named scanlines.

I wasn't even aware that people were using it wrong. The scanline is the light part, where the TV's electron beam went left-to-right, drawing pixels. Any black lines are a side effect of the excited phosphors not quite filling the space under the glass.

When you're emulating scanlines, you're drawing light pixels only on part of the screen. The black lines are a side effect. I didn't even think they had a name.

(edit: well, I mean, other than "black lines". )

[caad]

I agree with OP. Let's rectify this misconception.