Looks awesome. Is that SDR, then?
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Yes! Just added that to the post. My phone is super bright and has probably the best screen I’ve seen in motion outside of a CRT - it’s got a super AMOLED I think. All we need now is BFI support in the mobile Vulkan and we might be there - my phones display supports 120hz too.
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I got a chance last night to try out the shader on the Samsung S95B again and I managed to make some progress on Game Mode in that it now doesn’t scale the image.
What was going on was Windows behind RetroArch was swapping to 300% scaling for some reason. I just hadn’t known because I was in RetroArch and I must have tried all my changes inside RetroArch.
So this works a treat in terms of latency but I’m not sure it does much else for retro gaming.
What I really wanted access to is the display Black Frame Insertion which is termed LED Clear Motion. Sadly this is greyed out in ‘PC’ mode i.e when connecting your PC.
After a bit of reading I found you could fool the TV into thinking a games console was connected. Maybe that’s the wrong way to think about it - instead it maybe better to say I changed the mode of the hdmi connection from ‘PC’ to ‘Game Console’.
Regardless this enables the Clarity settings BUT at a major cost: chroma compression. Chroma compression destroys this shader because of the 100% mask it employs. I’ll post some photos to show but this is probably the reason half the people that use this shader gets poor results as it’s not obvious at all the TV is doing this in this connection mode - it’s only RTings mentioning that PC mode guarantees 4:4:4 colour.
Long and short it doesn’t seem you can have BFI with full colour 4:4:4 at the moment.
Reading across various sources I wouldn’t be surprised if this effects all Samsung TVs.
From what I can see though when it’s on motion clarity is comparable to my PVMs and it doesn’t appear to have that much impact on brightness but I can’t be sure because the colours are so screwed.
For the time being I’m falling back to RetroArchs BFI which has a dramatic effect on brightness but is more than useable on this bright display - it’s just not as bright as a CRT or with BFI off.
I’m going to try and follow this up with Samsung.
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This could be due to the TV automatically compensating in the brightness department when BFI is enabled. My 3D TV does the same when 3D is activated.
You don’t get this if you feed the TV a native line interleaved 3D signal though and since this doesn’t need the TV’s 3D mode to work, there’s no brightness compensation.
So when you’re using software BFI through RetroArch, the TV isn’t aware that it’s receiving a BFI signal so it wouldn’t automatically increase the brightness.
Just a theory.
Yes I’m lead to believe this is a different algorithm BFI in that it’s the same idea as backlight strobing (that LCDs do) where a rolling bar of black goes down the screen. We can’t do this sort of thing from RetroArch as we have transfer whole frames over the hdmi cable where as the TV manufacturers have much more control especially OLED manufacturers. This is where I think the majority of the brightness differential would come from, although absolutely power saving stuff could be kicking in although I’ve turned off as much of that stuff as I can/makes sense because of our more extreme use case.
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Hi there. I’ve been trying this shader out but it seems to be broken for me on my CX. No matter what settings I change, I always get an extremely dim and washed out image.
Previously I’ve been using crt-aperture with the global retroarch HDR and it got very bright, even with BFI. Using megatron with the same HDR settings set in the shader parameters though can’t come close to the same brightness for me, and while it can be a bit brighter through messing with the resolution and other settings, its still way darker than my old setup, even with that running BFI and no BFI on megatron.
Tried taking a comparison pic but I’m not sure how well it shows off the issue. Hopefully I’m not treading old ground. Read through most of the thread and saw someone else with the same issue but it was never resolved.
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Some level of darkening is to be expected, since it relies on the HDR brightness instead of blur/bloom tricks to light pixels when they technically shouldn’t be lit. It shouldn’t be washed-out, though, and that image looks to me like it’s not getting tonemapped properly. That is, it looks similar to how HDR stuff looks on non-HDR displays.
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Just to add on top of what @hunterk just said (and putting BFI to one side for a moment) you shouldnt be getting a washed out image: a few possible causes are as Hunterk said youre not using a full hdr pipeline as in its not on in windows and or in retroarch and or in the shader parameters.
Another issue could be you are not using a full colour 4:4:4 output from your PC (either due to high refresh or gfx card not supporting it or wrong output port from gfx card or wrong cable or wrong input port on monitor or your PC/app is just set to have sub-chroma compression on).
Another smaller rectification is to use the RBGW display output type in the shader parameters - it should be marked ‘OLED’ but its doubtful it will cause washed out colours. Also make sure you are using ‘colour accurate’.
Also try playing around with paper white nits (once you have set peak nits to the correct value as specified by say rtings.com) - whack it right up to peak nits for example. Both in the shader parameters (you should ignore the values for this in RetroArch settings->video->hdr menu for this shader).
Also if you are thinking HDR isnt on then using the shader in SDR mode (again in the shader parameters) should fix any washed out colours.
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Thanks for the advice. After doing some more tweaking, I’ve managed to get it looking much better. Biggest thing was changing the resolution in the shader parameters to 1080p, which does wonders for the image, but predictably loses detail with the shader itself.
Though while it looks nice, I still think something is wrong with my setup with regards to HDR somewhere due to an issue I forgot to mention before. I can’t seem to get perfect blacks in any scenario. Blacks will always come up grey no matter what is changed unless the image is darkened enough to be unseeable. Has anyone encountered this before?
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How do you have your TV set up? Did you rename your HDMI Input to PC and are you using Game Mode?
Did your TV update itself recently? After updates the Black Level setting is sometimes reset to Auto. Perhaps you can try setting it to Low.
Your TV scaling or Aspect Ratio mode needs to be set to Just Scan.
What about your Brightness Settings or Power Saving mode?
Also be careful with the Sharpness settings on your TV and also in your Graphics Driver Control Panel.
Try switching back and forth between GPU and Display Scaling mode.
Lastly, do you have HDMI Deep Color enabled for your HDMI Input?
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All of my settings are like that, yeah. I should’ve clarified, I get perfect blacks with every other shader and in general. Its just the megatron shader that turns them to gray.
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Yeah, I have had this same issue since the shader got updated some months ago. The image was perfect for me but then something happened and now everything looks washed out.
I’m using RetroArch on Xbox Series X so I have to force the HDR mode on from a secret menu on my LG CX OLED. RetroArch on Xbox doesn’t support HDR so I have to use this workaround.
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Thats definitely not right - using 1080p makes it better that is - Ive heard quite a few people report that. Usually its to do with using sub chroma compression but maybe its not and its some kind of tv post processing or something else is going on. I e heard quite a few people talking about screen interference when viewing high frequency patterns in older screens (theres a term for it but I cant quite remember right now) but part of me thinks this might be to do with compression techniques as well.
This shader is particularly sensitive to any kind of compression or post processing by the tv or any other part of the image pipeline because it uses 100% masks. I think if you turn off any blurs and have 100% masks in other shaders youd get the same thing happening - I would try to prove this theory but Ive never suffered this issue with any of the displays Ive used so sadly I cant.
Regardless lets ignore all that for the time being and just rule out HDR issues: turn off hdr in everything - windows, RetroArch and the shader parameters (by setting it to SDR). This will result in a darker image for sure but the colours should all be right and you should be able to use 4K and its associated fine grain masks perfectly fine (excuse the pun).
Then we can hopefully rule that out and progress from there. Id love to get to the bottom of this issue where ever it may lurk.
Obviously when using SDR its particularly critical to turn up the tvs brightness to max.
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Also what device are using to feed the image? A windows 10 PC with a nvidia 3000 series gfx card say?
Im sorry to hear that and hopefully I can fix it. Does using SDR mode fix the washed out colours?
Even the SDR versions seem to have raised blacks. I just noticed that the ”crt-sony-pvm-4k-hdr.slangp” shader (last one on the list) doesn’t have raised blacks, maybe this one didn’t get updated or something.
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Hmm ok so thats a really old shader preset. Im just wondering whether somehow youve got old settings for the shader parameters for the other presets. One thing to check is that ‘Gamma’ is set to 2.22 or 2.4 or somewhere around that range. ‘SDR: Gamma’ shouldnt make any difference when using HDR but should set to 2.4 when using SDR.
Since updating shaders doesn’t delete old ones and you’ve had quite a bit of churn on your presets, we might see if it helps some of these issues if they delete the shaders_slang directory altogether and re-download them from the online updater.
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Tried things out with SDR and all the same issues pop up unfortunately, from the washed out colors to the raised blacks. In response to the hardware question, I’m using a windows 10 PC with a 3090 and its outputting in 10bpc RGB. Changing the dynamic range between full and limited also has no effect on the black levels.
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Perhaps you can share some close up pics of the actual screen so that we can see what you’re actually seeing and try different presets as well if you haven’t already. Try them all. What are your Peak and Paper White settings?
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