Sony Megatron Colour Video Monitor

[colourofsound]

@MajorPainTheCactus @Azurfel

I’ve been loving the original presets for Megatron, especially now I’ve got Retroarch working in HDR on my LG BX.

I’ve been working on getting them going in Reshade on my Bazzite mini-PC build; and I’m having mixed results.

I’m interested to know what settings @MajorPainTheCactus uses in his show case video on Youtube with Dead Cells; and I’m also interested in a discussion about the best way to setup the CRT_HEIGHT resolution in order to get a decent CRT emulation whilst still making text in modern games more readable.

I got into this hole with Octopath Traveller, and I am finding with that it needs a close-to-native CRT_Height resolution and a high TVL to make the high resolution text in the game readable. I’ve gone with the JVC shadowmask preset on that game with the resolution settings matching the game; and whilst the effect is subtle it is worth it.

Another game on Steam which really benefits from a shader is Jack Move; and it looks great.

I was using the Guest Reshade port previously but its GPU overhead is considerable in comparison to Megatron, and on miniPCs you need all the power you can get!

Thanks again for all your work on this guys. /essay

[Wilch1]

Hi all, if anyone’s using a Radeon 6000 series on Windows, please check Megatron using aperture mask with the vulkan video driver. Any issues? On my machine, instead of a mask I’m getting a solid colour, sometimes red, sometimes green. If I remove the amd drivers the mask is fine, but obviously my gpu performance drops considerably until I reinstall the drivers. It’s only the vulkan or opengl video drivers in RA experiencing this, directx is fine

[Cyber]

@Wilch1 What display are you using? What’s it’s native resolution and subpixel layout?

What desktop resolution are you using? What preset or Shader Parameters have you tried?

Did you set the Display’s Subpixel Layout to match your Display’s subpixel layout?

Post some screenshots and / or photos of the screen so that others can see what you’re trying to describe.

Have you tried rolling back or updating your GPU Drivers to the latest version, including Beta versions?

Are you sure your colour format is set to RGB 4:4:4 Full for no chroma subsampling?

[bigretrofan]

I registered just to comment on this issue. I have 6900xt and same problem, when I use aperture mask whole screen is red color only. Other masks works normal, only aperture grill is not working properly. For me problem started when Windows 11 was updated to version 24h2 and it is broken ever since then, before that it was working fine. I also have win10 partition and it is fine there also.

[Wilch1]

I’m using LG OLED42C2 TV, native 4k, RGBW. Running at 4K 4:4:4 RGB full range. I’ve tried both RGB and RWBG subpixel layout, both look the same. Aperture mask at 300 & 600 tvl displays the image in red. 800tvl is blue and 1000tvl is magenta.

I’ve tried the aperture mask from other shaders without any issues including guest advanced. It’s only megatron and only the aperture mask, the others are fine. I’ve seen a similar glitches with limited RGB range and other mismatches before, but this is different. Everything is set up correctly. It only happened after installing a Radeon card, I was on nvidia for years before this.

I’ll try and get a picture, but basically the game graphics are mostly intact, except everything is just a shade of bright red, blue or magenta. There is no mask showing at all. It’s very odd…

[Wilch1]

I knew I couldn’t be the only one. I think there’s a driver regression or something. It looks fine with the AMD drivers removed, but that’s hardly feasible for gaming

[Cyber]

@Wilch1

I think there’s a driver regression or something.

You can try older drivers and see if the issue persists. See if you can track down which driver started the issue. Try removing drivers completely by using Driver Cleaner.

Another thing you can try to isolate the issue is using a Linux installation via USB or CD.

[Wilch1]

@Cyber

You can try older drivers and see if the issue persists. See if you can track down which driver started the issue

Can’t hurt to try. @bigretrofan when did the issue present itself for you, might be easier to track down a working driver. Unless a Windows update caused the issue as you alluded to.

@Cyber

Another thing you can try to isolate the issue is using a Linux installation via USB or CD.

Already tried linux and the shader works perfectly. Didn’t try the proprietary AMD driver though

Update: and to reiterate; this is a vulkan/opengl issue. No problems with dx11/12

[Cyber]

@Wilch1

No problems with dx11/12

In recent times I’ve actually been using DX11/12 in RetroArch you know due to the ability to enable Hard GPU Sync via Waitable Swapchain and setting Max Frame Latency to 1.

I don’t get these options when using Vulkan. Instead the lowest I’m able to set Max Swapchain Images to is 2, so unless I’m missing something, DX11/12 is currently able to achieve lower latency than the generally regarded as superior Vulkan?

I don’t seem to notice a difference switching back and forth between video driver APIs though. Some have stated that it’s possible to switch Hard GPU Sync On manually for Vulkan.

Well I haven’t seen that option in the RetroArch menu in many years but it can be added to the config file. Not sure if it actually still works. I tried adding it but the menu options never changed to what was available in DX11/12.

Hopefully someone more knowledgeable about this can confirm or deny whether or not there exists a potential 1 frame latency advantage by using DX11/12 over Vulkan in RetroArch currently.

So what I’m saying in a nutshell is that there may be some positive side effects if you have to settle for DX11/12 in the meantime as a workaround.

One con that I could remember was that Mega Bezel took much longer to load using either DX11/12 vs Vulkan. I’m can’t remember if that was ever resolved.

[Wilch1]

I thought vulkan already benefited from Hard GPU Sync hence the setting wasn’t required, but it’s been a few years since I looked into it.

I’d be interested to know about any frame latency differences.

I’m not averse to DX. I did see a delay in loading heavy shaders when I used them, but not with megatron. But some cores force a specific video drivers e.g scummvm forces opengl so I wouldn’t be able to use aperture there. I’m not really averse to using dot/slot mask with certain cores either, but I’d like to see ths issue fixed, as niche as it is.

UPDATE: I’ve found an amd driver which works: 24.5.1 with vulkan 2.0.299 from May 2024, although I might just live with the compromises rather than running an older driver…

[Cyber]

@Wilch1

UPDATE: I’ve found an amd driver which works: 24.5.1 with vulkan 2.0.299 from May 2024,

This is great and the first step towards resolving the issue permanently. The next might be to try to find the specific driver in which the problem started.

You can probably report it to AMD as well as the RetroArch dev team.

I’m not sure if you already did but can you restate the exact “Display’s Resolution”, “Display’s Subpixel Layout” and “CRT Resolution (TVL)” settings where the issue is occurring?

From this, I can look at the Subpixel Mask Layout to confirm if it is correct and we can also use this information to try the same Subpixel Mask Layout in another shader like CRT-Guest-Advanced to help eliminate the shader as also having an issue which might be contributing to the problem.

By the way, are you the same @Wilch who used to post here in the early days of Sony Megatron Colour Video Monitor when it was now getting proper WOLED support?

[Wilch1]

Looks like 24.5.1 was the last good driver then 24.6.1 introduced the regression. It was the first driver to include vulkan version 2.0.302.

Exact display res: 3840x2160.

Display’s Subpixel Layout: RWBG (not RGBW which I mistakenly said above).

CRT Resolution (TVL): Issue occurs in all with differences (300 & 600 tvl show a red image, 800 tvl shows blue and 900 tvl shows magenta).

RGB and RWBG mask subpixels tested with no difference.

Which mask in guest advanced would be the most similar?

Yep, same Wilch. I used to sign in using my github account, but lost access!

[Wilch1]

As you can see, there is no mask displayed, just shades of red, blue or magenta:

[kokoko3k]

Usually those kind of issues are due to gray documented areas, where the driver can act as it pleases.

And even if it isn’t, Retroarch is not that important to make amd invest resources to fix specific (like to be) bugs.

The best bet is to try to fix it by modifying the shader bits triggering it.

[Cyber]

@Wilch1

Which mask in guest advanced would be the most similar?

These are the Subpixel Layouts of the Sony Megatron Colour Video Monitor 4K Masks. I can get CRT-Guest-Advance’s Mask Layouts but at a later. Maybe @nesguy or someone else’ who knows can follow up in the meantime.

Off the bat I can tell you that RRGGBBX is Mask 12, RGBX is Mask 10 and RGB is Mask 6.

4K 


300TVL

RRGGBBX
RRBBGGX
BBGGRRX


600TVL

RGBX
RBGX
BGRX

800TVL

RGB
GBR
BGR


1000TVL

MG
YB
GM

Update: Here are CRT-Guest-Advanced’s Mask Layouts:

New CRT shader from Guest + CRT Guest Advanced updates

Hey @Duimon, here is the current mask list. If there are any uncertainties, just ask. -1.0: no mask 0.0: a dense magenta-green mask 1.0: Lottes RGB mask with a some sort of slotmask 2.0: Lottes RGB mask 3.0: Lottes - a bit enlarged and shifted RGB mask 4.0: Lottes - 2x enlarged and shifted RGB mask, looks nicer with 4k+ 5.0: a dense magenta green mask (trinitron mask controls) 6.0: RGB mask (trinitron mask controls) 7.0: Black-White mask (trinitron mask controls) 8.0: Black-White-White mask …

@Wilch1 Remember, to reverse the Mask Layout for WOLED and BGR Displays you can use Mask Layout 1 (BGR) in CRT-Guest-Advanced. The particular starting subpixel or subpixel offset is what allows CRT-Guest-Advanced’s Mask Layout 1 to be compatible with both BGR and WOLED Displays.

[Wilch1]

@kokoko3k

And even if it isn’t, Retroarch is not that important to make amd invest resources to fix specific (like to be) bugs.

So far it’s one mask within one shader within RA while using vulkan/opengl. Very niche indeed.

[Wilch1]

I tried every mask in guest-advanced at full strength, each with various mask sizes and with both mask layouts. No issues.

Perhaps @bigretrofan can try?

[Cyber]

@Wilch1

No issues.

Did you try with HDR On as well as Off in RetroArch? Also have you tested the Sony Megatron Colour Video Monitor masks showing the issue with the Shader Parameters set to SDR Mode and HDR turned Off in the RetroArch Menu?

Lastly have you tested my latest CyberLab Megatron miniLED Epic Preset Pack or @Azurfel’s, Azmods shader and presets to see if you’re also experiencing the issue there?

Mega Bezel also has Sony Megatron Colour Video Monitor base presets you could test.

[bigretrofan]

I tried guest advanced mask mask 10 and it is working properly on latest driver while Megatron is broken. I then downgraded AMD drivers 23.9.1 to check and there is is working as intended. So it is not Windows 24h2 upgrade as I originally was thinking ( my win10 other partition is using older driver so no wonder it was working there) but it fits timeline if drivers got broken in mid 2024 timeline as Wilch1 rightfully discovered.

[Cyber]

@kokoko3k

And even if it isn’t, Retroarch is not that important to make amd invest resources to fix specific (like to be) bugs.

We could still make the bug report to AMD and see what happens. It could be a genuine bug/mistake on their part and who knows what else could be affected by it?