It absolutely won’t work on an LG OLED as it has WRGB layout. It looks a mess sadly. So with the photo what do you mean by the shader off - as in using the stock shader with HDR turned off? I can certainly do that but I’m not sure what that tells us? The number one thing I think is to take some photos of your setup with standardized settings - ISO 100, shutter speed 1/60, WB 5000. We can then see what brightness your at compared to my pictures i.e it’s a direct comparison then.
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Yeah I’m not quite as pessimistic for a start there are already TVs that can reach 1800nits (Samsung QN90A) admittedly that’s over a small area but then we turn off most of the pixels so maybe we get away with it - it’s all about heat dissipation and not blinding people.
Then there’s new technologies like MicroLED and possibly even QD-OLED that might have much faster response times and so less need for BFI.
Also CRTs have pretty terrible motion blur anyway.
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It’s not about the TV having fast enough response times and trying to mimic the phosphor afterglow or persistence if a CRT. The BFI is a requirement if you want the mask detail to be preserved during motion and scrolling.
Haven’t you noticed what happens to the mask patterns on the parts of the screen that are in motion? Sorry to spoil the illusion and bring this to your attention if you haven’t noticed it but in motion the masks completely fall apart. Yes, after doing all of that hard work to find the perfectly matching subpixel arrangement. The only parts of the screen where this doesn’t happen are the static elements and you won’t notice it when you’re not moving or scrolling.
That’s not how a CRT worked at all. Despite phosphor trails, phosphor bleeding and afterglow the mask patterns remained physically and visually intact. Backgrounds remained sharp when scrolling and didn’t look at all like what we’re currently experiencing on non-BFI displays.
Sorry if you can’t unseen this now.
This is a different blur caused by the persistence of vision of the mask. In CRT’s only the graphics themselves will have blur due to persistence of vision not the mask.
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Oh no I have noticed that (you can’t really miss it) but I wouldn’t say that’s the main problem. The main problem for me is the noticeable loss of scanlines when moving around which isn’t to do with the mask (as far as aware) and which you see on a CRT too.
As things scroll you seem to start to lose the blacks on between scanlines too. Maybe it’s more an optical illusion on a CRT I’m not sure. Maybe it is on the LCD too?
So going back to the mask for a moment I’m not 100% sure why you would lose it: the same sub pixels are turned off as in they are always turned off, they never emit light the whole time you are playing. How is it they can contribute to motion blur?
I presume the answer might be a bit to do with light leaking but then surely you would see primary colours change colour as they moved because adjacent coloured sub pixels would bleed light?
I’m not convinced you do lose the masks. I can however totally see that happening when using dulled masks.
The darks in the scanlines are a bit different in that they do have a bit of colour to them when they are at 100% width so possibly the light bleed is happening there, that say blur busters is talking about( i.e the space ship is flying across the screen lightening and darkening each pixel).
BUT again the brightness of the scanlines are at a fixed positions on the screen mainly: I wonder if I see this issue with the thin scanlines of the 20L4 PVM shader. As in large numbers of always off pixels that never get turned on in between.
Im not sure BFI is the solution to the problem (in my shaders at least) to (100%) masks and (50%) scanlines.
I could be wrong on all this and I’m missing something in LCD tech but I will say I do see the same thing going on on my PVM (arguably to a lesser degree but I’m not sure)
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Maybe because they have to be refreshed and redrawn and during motion the colours of the phosphors would change and during these transitions between colours of the phosphors (due to motion) typical LCD motion blur due to sample and hold causing persistence of vision can occur. The BFI reduces this motion blur caused by persistence of vision. CRTs don’t suffer from this because they are not sample and hold displays. The whole process of drawing line by line with vblanks in between means that there’s very little in terms of a complete frame for our brains to remember (or is it our retinas to retain).
I notice it all the time once I don’t forget about it by being immersed and not paying close attention to how much better things like backgrounds look when not scrolling.
Perhaps @Nesguy can offer a better and more thorough explanation of this to you.
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Ive just confirmed what I was saying, this in my opinion is absolutely an optical illusion and as such is nothing in inherent in the display.
If you look at my CRT as you scroll in the vertical direction you lose the scanlines. If you go left right you keep them. If you do the same on an LCD with my shaders you get the same effect - it’s slightly lessened if you have larger black gaps between the scanlines.
What clinched it for me is that you can break the illusion by looking at one of the corners in the LCD - there is absolutely no loss of mask or scanline as you scroll. It’s purely an optical illusion that you get on both CRTs, LCDs and probably OLEDs.
You maybe able to help break that illusion with BFI but that is not what happened on a CRT. I will say I think the effect is slightly worse on an LCD over my PVM but then I’d argue it has slightly larger blacks gaps as the display is physically bigger.
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Precisely, persistence of vision happens in the eyes, retina and brain. That’s exactly what BFI mitigates. Full frame sample and hold display technology will facilitate this optical illusion much more readily than line by line scanning with vblank technology used by CRTs.
I’m waiting on @Nesguy or @hunterk to chime in on this one and fill in the blanks.
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Hi MajorPain. I don’t want to derail this thread but being that you’re the one who added HDR to Vulkan recently, can you look at my post I made?
There is serious problems when using BFI with HDR enabled. I put a video up to show what is going on.
Anyway back on topic lol.
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Hi great to hear from you! So I’m trying to find the post you made but can’t see it - where did you post it?
If you haven’t already can you tell me the make and model of your display? Also is everything fine when you don’t have BFI on? Also does what you are seeing happen with the stock shader and HDR on?
It’s this one:
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Hey just briefly again not to derail but it’s a 65 inch LG C1.
When I turn off BFI, it’s fine. If I keep BFI on and turn HDR off, it’s fine.
So it’s something with how HDR is interacting with BFI. Sadly I REALLY need BFI with my C1. The sample hold time is so instantaneous with motion that only BFI makes things smooth like butter.
Not using any shader at all. That video is with raw pixels and nothing else.
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So I’ve posted a reply but the TLDR is that I think this is your local dimming settings. Turn it off and see where you get to.
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C1 is an OLED TV so local dimming is every pixel. Can’t remember seeing any local dimming settings on my OLED TV.
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Are you saying that LCD motion blur is an optical illusion? I think you may want to do some further reading on the subject. Phosphor persistence on a CRT is definitely not the same thing as motion blur on an LCD.
This site has everything you’d ever want to know about lcd motion blur.
When viewing this on a crt the ufos remain perfectly sharp with no loss of detail. Not so on an LCD.
Anyway, I don’t want to derail the thread so that’s all I’ll say on the subject for now.
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We can break it off to another thread if needed, but I think what @MajorPainTheCactus was saying is not that motionblur isn’t a thing, but that the apparent disappearance of scanlines on vertical motion and masks on any motion is an optical illusion.
I’ve definitely noticed the same effect with my CRTs, so no matter what’s going on, it’s not just an LCD/sample-and-hold thing.
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Oh for sure, you lose scanlines when scrolling vertically on a CRT, but this happens when scrolling at a much slower speed on an LCD.
And yeah a new thread might be good, or the existing BFI/strobing thread.
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oh! I get this too. I didn’t connect the dots; just thought the issue was with my TV. I had to disable BFI. @MajorPainTheCactus
Here’s an example: https://1drv.ms/v/s!AmQUGfXPPtq7gw3q-vVZo46cCI5G?e=38B1Ny
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Yes thanks! I just remembered that on the other thread! 
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Ok right I see - thanks!
First let’s take this over to my Vulkan HDR thread.
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Yeah so that’s not what the discussion is about - LCD motion blur is of course a thing as in something scrolling across the screen like the spaceship.
What we’re talking about here is the loss of scanlines as you scroll vertically up and down and the mask which do not move.
With respect to my shaders which use black in both cases they are all in fixed positions. As in during an entire play session using the same shader those pixels and masked subpixels never emit light.
So as an experiment if I put two pieces of paper over the screen (LCD or CRT) and just show the black in between the scanlines there is no motion blur caused by scrolling vertically because the pixels never emit any light.
However when you look at the screen without the pieces of paper you absolutely see motion blur as if those black pixels suddenly were turned on. This is very different from the spaceship flying across the screen and traditional response times where a pixel has to change colour radpidly.
Where things get complicated:
What I will say is that I’m not sure I fully understand this optical illusion as it’s definitely worse on an LCD than a CRT. This may well be to do with how LCDs work compared to say an OLED (OLED being near instant on off Vs LCDs much slower blind over a window opening type thing) and BFI is helping the LCD mirror an OLED better which breaks the illusion more. But CRT phosphors are known also to persist as in phosphor after glow so maybe that’s not contributing to this effect. Also why would OLEDs suffer from it? All questions I have yet to answer.
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