Yes youre both right - ill find some time - theres only a few small changes but they are quite important!
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I’ve been trying to get these up and running with my new HDR monitor (Innocn 27M2U-D) but I’m having some sort of issue that I haven’t been able to get to the bottom of. With various Megatron shaders (including Cyberlord’s versions) the resulting image is always dark and kind of brownish grey - nothing like the nice photos I’ve seen in this thread and nothing like the CRT I’m comparing it against. I was, however, able to get a sort of okay looking image out of a couple of Cyberlord’s presets but the color was really bizarre looking - overly lime greens and garish bright reds.
I have HDR turned on in Windows and Retroarch, my nvidia settings are pretty much at defaults for my 3070, and the shader parameters are set to the default settings. I’m running the Steam version of 1.16.0. I can tell that HDR is on in retroarch because the menu looks obviously different and box art images are clearly not SDR. Other HDR content outside of retroarch looks fine on the display and doesn’t have any obvious color or brightness issues. It even gets eye-searingly bright sometimes. I’ve also gone through HDR calibration in Windows.
Other non-hdr specific retroarch shaders look great with fairly accurate colors and are plenty bright even with scanlines so I don’t think it’s an issue with the brightness or color reproduction of the display itself (but who knows, I guess. I don’t have another HDR display to try it on). I’ve tried D3D12 and Vulkan and it seems to look the same either way. I’ve also spent some time messing around with the shader parameters and tinkering hasn’t really gotten me anywhere. I took a few HDR screenshots that should hopefully illustrate what I’m seeing (if this is a lousy way to demonstrate I could try taking pictures of the display):
SMW: https://mega.nz/file/33gxiKxI#s922T5x_KCK18CzO6Y64lPJJ0ktFvperp8MvYtljqKI
Super Mario Bros NES: https://mega.nz/file/nvZXwTSR#UYy4A6bE3Mmzfsw86vIgKHO3wushZKdyr40mAKaQ-3g
Any idea what might be going on? Thanks
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Those screenshots look fine on my system, which suggests that it’s an output or display setting problem.
It kind of sounds like it might be chroma subsampling? Double check that you have 444 chroma working in HDR at the same refresh rate you are using for RetroArch: https://www.geeks3d.com/20141203/how-to-quickly-check-the-chroma-subsampling-used-with-your-4k-uhd-tv/
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For a more complete representation of what you’re experiencing, good quality photos of the screen should definitely help.
What NES Palette are you using? I use Sony CXA2025AS.
I only got a chance to look at the SDR versions of the images so far but I don’t expect the HDR ones to tell a different story. I would have to concur with @Azurfel. I don’t see anything inherently wrong with the images in the jxr screenshots you shared.
You mention Windows HDR Calibration. Does that even have an effect on Sony Megatron Color Video Monitor?
Did you adjust the “Peak Luminance” and “Paper White Luminance” settings to match your display?
Also, did you adjust the “Display’s Subpixel Layout” setting to match your display?
Did you remember to update your Slang Shaders as well as install the recommended version of CRT-Guest-CRT-Advanced-NTSC?
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Essay incoming: I think I’ve got my issue figured out and I believe it was mostly thanks to me misunderstanding some things but I’ll elaborate for anyone else who comes across my posts here in the future:
It kind of sounds like it might be chroma subsampling? Double check that you have 444 chroma working in HDR at the same refresh rate you are using for RetroArch: https://www.geeks3d.com/20141203/how-to-quickly-check-the-chroma-subsampling-used-with-your-4k-uhd-tv/
Thanks, I checked this and it looked fine to me so I think I’m set correctly there.
What NES Palette are you using? I use Sony CXA2025AS.
I tried a bunch but couldn’t settle on one that I thought looked right. I switched to Sony CXA2025AS and it actually matched the look of my NES on my CRT very closely so I’ll leave it there. Thanks for the suggestion.
You mention Windows HDR Calibration. Does that even have an effect on Sony Megatron Color Video Monitor?
I think it must - it creates a color profile which I believe is used system wide.
Did you adjust the “Peak Luminance” and “Paper White Luminance” settings to match your display?
I spent a lot of time messing with Peak Luminance but didn’t really tweak Paper White Luminance very much (for some reason I thought I would need to keep it pretty low - I guess because the default settings are 800 / 200 so I was staying close to that ratio). I found that by setting Peak Luminance to my display’s claimed number and putting Paper White Luminance close to that value or 200 to 400 points under it I got much better results. I believe this was my main issue.
Also, did you adjust the “Display’s Subpixel Layout” setting to match your display?
I’m not really sure about this one. The monitor is a mini LED IPS but the manufacturer barely has any information available. Regardless, I tried the different settings for this in the shader parameters and none of them seemed dramatically different when viewed from a few feet away at least.
Did you remember to update your Slang Shaders as well as install the recommended version of CRT-Guest-CRT-Advanced-NTSC?
I did do this and I believe everything is installed correctly.
So, I believe I had a few different things going on, none of which are the fault of the shaders.
- Windows 11’s HDR implementation is finicky and really likes to drop out of the HDR mode completely or get stuck in some weird halfway mode where greens and reds are totally blown out but everything else looks dark and strange. This seems to be exacerbated by me going back and forth between retroarch cores and shaders that may or may not support vulkan/d3d12/d3d11. It is really easy to get Windows stuck doing this and the only way to fix it is toggling HDR back and forth to reset it. Probably also need to restart retroarch and maybe even Windows itself if the issue persists
- As I mentioned earlier, I didn’t try setting Paper White Luminance high enough. Once I did this, it fixed my problem with the dark output (at least once the Windows HDR problems were sorted).
- I think I kind of misunderstood the objective of these presets. I think for some reason I was expecting a general one size fits all sort of reference image but the real goal is to recreate the appearance of these very specific models so of course things are going to look different than the cheap CRT I’m used to.
So, for anyone with this monitor (Innocn 27M2U-D) or similar I had especially good results almost out of the box with the sony-pvm-2730-hdr and jvc-professional-TM-H1950CG-hdr presets.
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It’s probably RGB given the layout used by a different model from the same line. (see the RTINGS INNOCN 27M2V review Text Clarity section.)
Semi-relatedly, you’ll also want to make sure Megatron is set to Colour Accurate mode and “Original” for Original/Vivid.
Just to verify, when using HDR shaders, you have HDR enabled in RetroArch’s settings, and you are turning on HDR in Windows before you start RetroArch?
Also, look into using CRU to restart your GPU driver. Much simpler than fully restarting every single time something weird happens.
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what kind of tv should i buy to not deal with mask layout issues, a normal 4k hdr tv?
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It’s probably RGB given the layout used by a different model from the same line. (see the RTINGS INNOCN 27M2V review Text Clarity section.)
Semi-relatedly, you’ll also want to make sure Megatron is set to Colour Accurate mode and “Original” for Original/Vivid.
Thanks, I wasn’t sure which settings to consider the default for those.
Just to verify, when using HDR shaders, you have HDR enabled in RetroArch’s settings, and you are turning on HDR in Windows before you start RetroArch?
Yeah, that’s correct. I’ve just been leaving it on in Windows and Retroarch. Seems to mostly stay set correctly if I don’t do anything weird inside of Retroarch.
Also, look into using CRU to restart your GPU driver. Much simpler than fully restarting every single time something weird happens.
Just checked this out and it looks like a handy tool. Will give it a try the next time things go weird.
Thanks for your all of your help (and Cyber as well). I appreciate it!
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I got both Displays today:
Unfortunately the company didn’t send me the ordered Mini-LED panel “BOE NE156QUM-NM1”, despite telling them before ordering, that I need the exact same model and not any alternative.
The OLED display is correct though.
Second problem is, that the controller, which I ordered from another seller, did arrive a week ago in germany, but the delivery person from the Hermes parcel company just scanned the package twice on two different days as “refused from receiver”. On both days I was 100% at home and he didn’t even ring the bell…
Thanks to this guy, the package with the controller is on the way back to china and the seller from china thinks I really have refused the package, which is not true.
I am a bit exhausted after getting a wrong display and no controller board as you can imagine and am kind of tired of ordering everything again.
@ snoring
You got a really nice Mini-LED monitor, which I had also in my mind before ordering the Notebook displays, it was just too expensive at nearly 700 euros for me.
What is your opinion with the shader now and can you maybe post some screenshots? I am pretty curious how the shader looks on such a bright Mini-LED monitor.
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I’ve really been enjoying it. Wasn’t too sure at first… it looked nice but is a lot bigger than I’m used to. Got over that pretty quickly though and it’s been great. The shaders look great on it too, though I haven’t spent too much time tinkering since I got a couple looks that I like for what I’m mostly playing right now (SNES). Took a few photos with the pvm 2730 preset (although I’ll say that these photos don’t really do it justice and my phone’s camera had a pretty tough time here. It looks much more vibrant and bright in reality.)
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I think this is my biggest complaint honestly with the varients of this shader. I have a 48" OLED and the pixels look much bigger than they should be. If I play around with the scanline settings I can get it looking more “normal”, but by default everything looks enlarged for some reason almost like a dot-matrix grid.
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I have Bgr pixels and either picture is dark and washed out or too bright and washed out. why can’t I figure out your parameters at all the instructions are very limited.
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There is a shader parameter for that. It’s called “Display’s Subpixel Layout”.
Did you research your display’s Peak Luminance Value?
What display do you have and what Peak Luminance and Paper White Values do you have set in the Shader Parameters?
It’s easy, just look up your display in RTINGS or any similar review to get an idea of the Peak Luminance. If you can’t find a review then you can try the specs sheet.
You have to load up a Shader Preset, enable HDR in RetroArch Video settings if it isn’t already enabled, then go into Shaders, Shader Parameters and look for the Peak Luminance and Paper White parameters.
Enter the Peak Luminance value you got prior then set the Paper White value to what looks best to you.
You can also try out CyberLab Megatron Death To Pixels Shader Preset Pack which might have higher defaults which might work better out of the box on certain displays.
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I spent a great deal of time last night playing around with the HDR shaders. I have a 77" C2 LG OLED mounted directly above my CRT Sony F310V and used it as a reference to dial in my parameter settings. I simply could not get my OLED to match the saturation of my CRT no matter what I did (spent about 2+ hours) but got really close. The size of the pixels/scanlines still really bothers me on larger screens, it just looks “off” to me without using 1000TVL. I decided to bust out my RTX 4090 Lenovo Legion laptop that has a 16" 2K HDR screen and I was blown away at how good it looks on a smaller screen. Compared to my CRT they are nearly identical in every way which really surprised me given the OLED is a much brighter panel, and the pixel structure looked smaller like an actual CRT (assuming b/c the size of the screens). I took some pics, if I get time I will upload them but for those struggling I suggest maybe trying a different screen if you have one available to you before giving up on your settings.
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You can also try to set the resolution to 8K and TVL to 800, this results in finer pixels / scanlines and is comparable to a 400 TVL CRT. This is the setting I use most of the time.
Some comparison pics would be nice with the 16 inch OLED and Sony F310V CRT 
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Holy crap, that actually worked! I didn’t get any of the 16" Laptop with the CRT, I’ll see if I can grab some and also go back and redo my 77" shots mounted above the CRT since last night the pixels looked larger since I was using 4K res.
Ty for the tip, I can’t believe how much better it looks on this TV now!
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Discounting the gamut overshoot bug, Megatron currently limits, clamps, clips, and/or compresses colors to Rec709, even when the selected Color System/Phosphor primaries fall outside Rec709, which could be contributing to the saturation issues you are observing.
Consider giving my gamut fix testing fork a try.
When testing this, make sure you set Mask Accurate/Colour Accurate to Colour Accurate, Colour System to r709, and Phosphors to NONE.
The gamut that most closely matches your FV310 will probably be either Apple RGB or Rec601.
(Despite the name, Apple RGB was actually based on the phosphors used for at least consumer Trinitrons from the early 80s until the late 90s/early 00s, and possibly until the very end on consumer models. The FW900 and possibly other pro level Trinitrons from the early 00s used SMPTE/601 phosphors tho.)
If you do try out the fork, please report back with your experiences. (The Shader Parameters option obviously needs work before mainlining these changes is even considered.)
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OK, guys, I still think this topic deserves better information for laypeople. We need a guide! 
Sorry, I need help.
I’m in my first experiences with Megatron, I have some doubts. If I repeat questions already asked, forgive me.
According to Rtings, these are my TV specs. I have circled the peak values. Are these I have to consider for peak luminance?
Should I set the peak luminance and paper white values in Retroarch’s HDR menu, in the shader parameters or both?
Do I have to adjust something regarding DCI P3?
Which TVL resolution is correct for 4K and 1080 respectively?
What aspect ratio do I have to use? Can I force 4x3 or is it better to use native Core?
Can I use screen curvature with Megatron shaders?
The SDR presets always have more vivid colors here. Is this right? Should I switch between them depending on game content (older game consoles)?
There are a number of other parameters. Should I consider any in particular?
Thanks!
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Most of us are using Peak 2%/10% as far as i know.
Your display’s bizarrely low 2% in game mode might make it uniquely unsuited for Megatron tho o.O
You need to have HDR enabled in Windows and in Retroarch’s HDR menu, but Only the shader parameters settings will effect Megatron beyond that, That said, you can reuse Megatron’s settings in the RA HDR menu for other overlay shaders that don’t support HDR if desired (other CRT shaders, LCD grid shaders, etc.)
You shouldn’t need to adjust anything in HDR.
In SDR you need to set “SDR: Display’s Colour Space” to P3 if that is your display’s SDR gamut.
There is no “correct” for TVL in Megatron strictly speaking due to the nature of what we are doing here. Blindly matching TVL to the specs of old CRTs doesn’t really work due to the size difference. Bigger CRTs had higher TVL for a reason.
Pick what looks good to you. For what it’s worth, on my 48" C1 at 4K, i use 600TVL.
I use the core AR settings with integer scaling unless they don’t scale properly (bsnes, for example, doubles the reported resolution for integer scaling purposes, resulting in an effective 8x scale at 4K rather than the correct 9x.)
No. Megatron works by taking advantage of the display’s subpixel layout.
“SDR: Display’s Colour Space” should be set to match your display’s SDR gamut if you are running in SDR mode.
In HDR mode, “SDR: Display’s Colour Space” shouldn’t have any effect. The Colour System/Phosphors settings are what you want to change depending on the content.
(As mentioned elsewhere, the Colour System/Phosphors settings currently don’t properly exceed the Rec709/sRGB gamut when when they should, but you shouldn’t worry about that if you are just getting started.)
Make sure you match “Display’s Subpixel Layout” to your display’s actual subpixel layout.
Mask Accurate/Colour Accurate should always be Colour Accurate in my opinion, but at least Cyber is more bothered by the effect that has on the mask than they are by the color inaccuracy, and you may be too. It’s ultimately your preference.
HDR: Original/Vivid should be Original for Rec709 primaries. Vivid is a weird “expanded” version of Rec709 made up by someone at Microsoft.
Personally, i prefer to set the shader parameters white temperature to 6504 for both D65 and D93, and adjust color temperature on my display instead. The result looks more like 9300k on my actual CRTs. But once again, this is ultimately your preference.
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Thank you for taking the time to respond. I’ll do as you suggested and follow this thread more closely.
I disabled game mode on the TV because it causes flickering. I’m not sure if it’s necessary for Retroarch.
Could you help me find the correct gamut?
I still don’t understand when I should use SDR or HDR in "[YOUR DISPLAY’S SETTINGS]. Does this have to do with the source of the content?
Also, which shader preset should I use? SDR or HDR variant?
Where did you see that information?
Here is the Rtings link for my TV. You can consult and if you find anything relevant, I will be grateful if share it with me.
Thanks!!
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