Blur Busters Forums

thatoneguy wrote: ↑

22 Feb 2022, 17:31

"Scanline" is mostly a terminology thing.


Anyways, I have this theory that the TVlines(Horizontal Resolution) of a CRT should match the resolution of the incoming signal(e.g typically a 320x240 window for retro). A coarse dot pitch also helps things too for low res.
To better illustrate what I'm talking about, look at the video below(timestamped) where Final Fight is displayed on a Shadow Mask PC CRT Monitor windowed in 1/3rd of the screen and look at how smooth it looks.

We're kind of getting off topic but you can see a Virtua Fighter Arcade preset at the link I posted above showing very wide scanlines that don't have blanks/dulling in between: https://forums.libretro.com/t/sony-pvm- ... /36109/456 but it's still made up of scanlines.

thatoneguy wrote: ↑

22 Feb 2022, 16:02

As for why this seems to happen on OLED I have no clue but it might be because OLEDs have very fast pixel response time + the pixel themselves are typical squarewave pixel control like any digitial display as opposed to the analog phosphor fade but that's just speculation on my part.

I think there's multiple prevailing factors, as explained in my post, which also applies to OLEDs, not just CRTs.
While OLEDs does produce more color saturation to compensate for OLED's lack of nit headroom, the same issues still apply.

Also as yet another factor, PVM's pulsewidth is very wide -- so it only reduces motion blur by about ~50%, not by ~90-99% like a CRT or a very good strobe backight (or a 1000Hz rolling-BFI emulation). Many OLED PVM's are 7.5ms pulsewidth, which only reduce motion blur to (7.5ms / (1/60sec)) = approximately 45% of the original motion blur of 60Hz sample and hold. That's still a lot of motion blur, and thus, what I described in my earlier post is still applicable during OLED PVM pulsing.

Global and rolling scan has no effect on the vision effects described in this thread.

I'll await MajorPainTheCactus' reply to my original long reply first to add more information --

Chief Blur Buster wrote: ↑

23 Feb 2022, 17:37

Also as yet another factor, PVM's pulsewidth is very wide -- so it only reduces motion blur by about ~50%, not by ~90-99% like a CRT or a very good strobe backight (or a 1000Hz rolling-BFI emulation). Many OLED PVM's are 7.5ms pulsewidth, which only reduce motion blur to (7.5ms / (1/60sec)) = approximately 45% of the original motion blur of 60Hz sample and hold. That's still a lot of motion blur, and thus, what I described in my earlier post is still applicable during OLED PVM pulsing.

Yeah I know that, and Fudoh(the guy from Shmups) knows that too which is why I find his "OLED Sample and Hold and CRT both are about as smooth as each-other" claim very odd.
But the whole "scanlines appear solid during lateral movement with Rolling Scan OLED but not with CRT" comment is very curious nonetheless. It might be related to blooming issues(CRT's stretch or expand their beam or whatever during brighter scenes)....as we know there's no such thing as a CRT with 0 blooming so that might be one explanation as to why the blank lines disappear during movement.