Another thing to try from this thread are the chroma test images from the first reply: https://www.reddit.com/r/nvidia/comments/ubm2bg/how_to_set_up_3090_to_output_10_bit_colour_for_lg/?utm_source=share&utm_medium=android_app&utm_name=androidcss&utm_term=1&utm_content=share_button
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You say you’re getting raised blacks. Do you have your Black Level setting on your TV on Low, High or Auto? You can try setting it to Low and see if that gives you the black levels you desire.
Also beware of Power Saving settings as they have a significant effect on overall brightness.
I know of at least one RetroArch user who uses AutoHDR.
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Yeah, Black Level is set to Low.
Someone uses Auto HDR with RetroArch on Xbox? I don’t know how that would be possible.
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Tried a number of suggestions mentioned earlier. I’m running at 4k/120hz and had deleted my slang folder when it was first suggested. My TV has already been set to PC mode and also changing the refresh rate to 60hz didn’t have an effect.
I took some pictures that major asked for, though I’m not sure how well it comes across on cam. I used crt-sony-megatron-default-hdr with all of the default parameters for these pics. Basically, when it comes to the black levels, all of the megatron shaders I’ve tried, whether its labelled hdr or sdr, exhibits raised black levels with none of the parameters fixing this. Hopefully these pics help: https://imgur.com/a/HkUJNCe
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Fantastic pics thanks. Comparing yours to Scarfs it looks like youve got different problems with Scarfs colours being off - what do you think? Im going to try reproing this on mine - the last two images look like they are of sonic and knuckles? Is that right? Whats the difference between the top and bottom images? I can see what you are talking about in the bottom pic. Let me look at this exact screen whatever its of. Again many thanks to you and @scarf for preserving with this.
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@barack-ojama and @scarf so Ive managed to repro both your problems.
A bit of background I have 5 displays I use to test on: Eve Spectrum (4K IPS HDR 700 nits), Samsung S95B (4K QD-OLED HDR 1000 nits), BenQ EW3270 (4K VA 300 nits), Dell XPS laptop (4K IPS SDR 600 nits), OnePlus 8 Pro mobile phone (1440p AMOLED SDR 1400 nits).
Ive gone into the 240p test suite and selected the grey ramp test pattern which shows two black to white and vice versa gradients across the screen. When I adjust the paper white and peak luminance and then the CRT gamma values to get a perfect black to white gradient on my BenQ because its so dark I have to have the paper white value right up to the peak luminance (of the monitor which is basically 250ish nits) and thus I need to compensate with a really high gamma value.
This I think gives the washed colours on that display which is what scarf is seeing when I look at the pure red, green and blue test screens. Lowering the paper white value and reducing the crt gamma seems to fix it in my limited testing at the cost of brightness.
On my Samsung S95B because its so bright I can have paper white around 200-300 nits (peak at 1050 nits) and a crt gamma of 2.22 giving perfect blacks and pretty bright whites and thus all the colours are vivid. Im yet to test the other screens I have - Ill first give you a report of my mobile phone.
Long and short is to play with those three settings and Ill have a think to see if there is anything I can do to help matters.
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So my OnePlus Pro 8 which has a whopping 1400 nits in SDR has a perfect gradient with SDR gamma set to 2.4 and CRT gamma set to 2.22. It also has very vivid colours. An amazing screen if Im honest.
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Changing those settings doesn’t have much of an effect for me unfortunately. I think it might just be the panel type itself; perhaps something about LGs OLEDs specifically (BGR pixel structure or something maybe?). I plan to get a new TV this year so I’ll end up playing around with this shader more when that happens. Big thanks to everyone for all the help.
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Are the SDR versions showing perfect blacks for you guys without LG CX? It really doesn’t make any sense to me how the SDR version can have different black levels on different TVs.
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My oled seems fine with this shader (LG C2 42 inch).
It supports full 4:4:4 at 4k, not sure about the C1 or CX, but here’s my settings:
TV: Hdr Brightness - 100%, Dynamic tone mapping - HGiG, Video range (black level?) - auto, BFI - off, Input label - PC, HDMI deep colour - 4k (on)
Nvidia control panel: (desktop in sdr), 10 bpc, Colour format - rgb, Dynamic range - full,
Megatron: Sony pvm 2730 hdr, Peak luminance - 720, Paper white - 250, Subpixel layout - rwbg
I don’t have hdr on in Windows 11, just RA using vulkan. I had to enable hdr in Windows first when using directx in RA.
Here’s some photos: (colours look more saturated in person)
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Here’s my picture with the same settings on RetroArch/LG CX.
EDIT: A better picture where Link is not in the dark:
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I just checked 240p test suite and realised the blacks are grey here too (using the shader). If i set the black level to low or raise gamma it improves. Need to tweak this some more. If i set black level to low without the shader i lose some colour gradients as expected, but enabling the shader returns them. The tv panel reports rgb 10bit.
Also some presets including default cause the blue bar to lose about 6 gradients regardless of black level
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Thats almost certainly the gamma settings (which includes those luminance values when using HDR). Have you definitely put paper white right down - a third of peak say and then play around with the CRT gamma (not the sdr gamma). Every single one of displays will show black at some setting of those three values.
The only other options are your TVs settings artificially making it grey or the black isnt black and is some very dark grey (you can test this by turning off the shaders and just screen grabbing the window and checking the values).
Failing that its all very odd.
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Try playing around with CRT ‘Gamma’ in the shader parameters as well. You definitely should be able to get pure blacks at the cost of brightness.
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Thanks for these settings @Wilch - its difficult to diagnose without the TV. It does look a little washed out though still - is that just the camera as you mentioned?
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Is this any better for you?
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My LG CX is properly calibrated so I doubt it’s the TV settings. Every other CRT shader has pitch black blacks and so did the Megatron shader before one of the updates that changed something.
The last Link to the Past pictures I posted also had greyish blacks. But this is not a big deal since now I know how to fix it.
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Is that in HDR that all the other shaders have pitch blacks - if so what are the gamma values and what settings do you have in the RA->Settings->Video->HDR menu?
Thinking about this I am going to check a few things as really black should be black always as its zero but there are cut offs in the rec.601/709 gamma standard that treats very darks and blacks differently and this could be where the dark greys are coming from with high gamma’s.
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Just also to add you can have more normal gamma values on low brightness displays with other shaders as they are inherently brighter. However you should definitely be able to get black black regardless in the Megatron - it will just be much darker overall.
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