Any CRT flicker tests on YouTube?

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Any CRT flicker tests on YouTube?
by on (#111160)
I am working on a GameBoy game with similar flicker effects as seen in some topics here. I'm curious how this would look on a Super GameBoy played on a classic CRT television screen, as the goal of my project is to make a game that could have conceivably been released in 1996.

I've also noticed that different kinds of flicker (vertical lines compared to horizontal lines compared to diagonal lines) produce better effects on my LCD computer monitor than others. So I would like to find the optimal flicker that is the most acceptable.

As I do not currently have an old CRT TV, I'm curious if anyone has tested on this, and if there are any videos online I could review.

The flicker effects in my GB project will create additional gradients beyond the native four scale grey.
Re: Any CRT flicker tests on YouTube?
by on (#111162)
YouTube maxes out at 30 fps and won't properly display high-motion video. Either every other frame gets dropped, which looks like frameskip, or odd and even frames get averaged, which looks like LCD blur.
Re: Any CRT flicker tests on YouTube?
by on (#111163)
You're talking about the combination of spatial and temporal dithering, right? Here's basically the tradeoffs:

Spatially: vertical and 1:1 diagonal dithering pose problems for anything with a color TV and composite video stage. Too high of a horizontal resolution and the dither will cause chroma crosstalk. Since I think the Super Game Boy just pads the gameboy's native 160x144 to the SNES's 256x224, you'll end up with chroma errors analogous to the ones demonstrated in this thread.

Horizontal dithering ≈works, but is (IMO) quite visible. If you combine it with temporal dither, LCD HDTVs that don't understand 240p input will assuredly combine fields in an obnoxious (highly visibly wrong) manner.
Re: Any CRT flicker tests on YouTube?
by on (#111164)
For the record, horizontal and checkerboard patterns did NOT work on the actual GameBoy for some reason. It produced inconsistent effects, either too light in some areas, or casting vertical shadows in others (as the LCD seems to darken other pixels on the same line if there are a lot of black pixels).

If a developer made a GB game in 1996, I'm guessing they would consider how such effects would look on the Super GameBoy, as they wouldn't want them TOO distracting.

I've found that diagonal lines 2 pixels thick work best on both the real hardware and on the LCD screen with an emulator. But, as I said, I have no clue how that actually looks on a CRT TV. I don't think anyone has done a NES pattern 2 pixels thick diagonally.

But all this is really just an extra consideration, as the effects are looking great on the real hardware. But my project would feel less authentic if I also didn't factor the Super GameBoy into my considerations.
Re: Any CRT flicker tests on YouTube?
by on (#111165)
psc wrote:
I've found that diagonal lines 2 pixels thick work best on both the real hardware and on the LCD screen with an emulator. But, as I said, I have no clue how that actually looks on a CRT TV. I don't think anyone has done a NES pattern 2 pixels thick diagonally.
Do you mean 2w2h? 2w1h? The last page of the thread I linked has a demo of 1:1, horizontal, and 2w1h. (Use nestopia with the NTSC filter. Or does byuu's bsnes higan support real NTSC filtering? If so, he has a SGB emulator in it, so you might be able to test that way)
Re: Any CRT flicker tests on YouTube?
by on (#111166)
lidnariq wrote:
psc wrote:
I've found that diagonal lines 2 pixels thick work best on both the real hardware and on the LCD screen with an emulator. But, as I said, I have no clue how that actually looks on a CRT TV. I don't think anyone has done a NES pattern 2 pixels thick diagonally.
Do you mean 2w2h? 2w1h? The last page of the thread I linked has a demo of 1:1, horizontal, and 2w1h. (Use nestopia with the NTSC filter. Or does byuu's bsnes higan support real NTSC filtering? If so, he has a SGB emulator in it, so you might be able to test that way)


I would love to test the GB rom in a Super GameBoy emulator with NTSC filter. Only problem is I can't figure out how to get the Super GameBoy to work with Higan. I got the boot rom from Costis' site and the Super GameBoy rom, but Higan keeps saying it can't find the boot room, even after I tried renaming it different things.

This thread seems to cover it, but so far hasn't worked for me: http://forum.themaister.net/viewtopic.php?id=334

Maybe eventually it won't be so hard to use :/
Re: Any CRT flicker tests on YouTube?
by on (#111167)
If you want to try out Super Game Boy emulation, try BSNES version 0.77.
Re: Any CRT flicker tests on YouTube?
by on (#111170)
If you've got a GB ROM I could probably run it on my SGB / PAL SNES, record the composite signal on my PC and put an AVI file online (I think my capture card supports 50 fps). I can't show you what the video would look like on a CRT though, as I threw away my old 14" CRT TV a couple of years ago.