Sony Megatron Colour Video Monitor

So I just made a school boy error and didn’t have my linear space colour in a high precision format. Just shoved a float_framebuffer into the slangp and boom sorted all the glitches at the low end. There’s been a few other minor nips and tucks elsewhere also but I can’t remember off the top of my head.

This shader basically uses everything as sigmoidal as 1D berzier curves are subset of sigmoidal curves. However I will say my curves are tuned towards better accuracy in the middle but don’t go as extreme as say what is used in Dogways but I figured that was better anyway in the general case.

Your settings will be heavily dependent on your display to be honest so it’s case of tweaking them for your TV or changing your TVs settings. I’ve just made sure the values pumped out make sense as in the stepping when going through the appropriate gamma curve. HDR is a whole different ball game of course.

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I presume you’re talking about Dodonpachi - I can’t easily see what you’re replying to? To 1CC that is incredible I think I can probably get to quarter of the way through the first level at a push. :rofl: Brilliant game though. That monitor is an Eve Spectrum - it’s infamous for being created by Eve who have now changed their name to Dough because their rep at delivering the goods was so bad. :rofl: But it’s a great display when you eventually get it and it’s amazing design. Blur Busters also tuned it so there’s a backlight strobe option but that only works in SDR because it makes the display so dark. It certainly has it’s foibles as mine starts to blink every so often (once every few days of full use) but switching it on and off again fixes it and the regular bios flashes change this behaviour every time - they seem to fix one issue and introduce another but it’s the only monitor that really brings in new features with every flash so there’s that. The stand is really amazing to in how easy it makes it to go vertical - better than most at least.

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Yeah, used to be a bit of a prodigy back in the day, now I’m just an old burnout. 1CCing Dodonpachi definitely stands out as one of the crowning achievements of my life, lol. Mastering it was a very rewarding experience. At a certain point you’re reacting so quickly that it feels like you’re no longer in control - some other part of your brain is calling the shots. It’s bordering on transcendental.

That monitor looks very nice. I see that it’s a glossy screen, too! That’s perfect. Thanks for the recommendation! I know what Santa’s bringing me this year.

What’s the rest of your setup like?

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I’ve always wondered that - if its an altered state of mind. The nearest I’ve got to it is in long distance running where you can get into a trance like state to overcome the pain or “the flow” or “plugged in” when coding. Love all that stuff.

One thing I would warn you about the monitor - it’s HDR performance isn’t great - it’s not got too many dimming zones. You can see this obviously to the blank sides of the screen but I don’t find I notice it too much playing games.

Definitely go on the forum and read the comments good and bad.

As for the speakers they’re Yamaha HS8 monitors and the accompanying subwoofer out of shot. All I’ll say is make sure you’re neighbours are far away. :rofl:

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This was me with Gate of Thunder, Lords of Thunder and Super Star Soldier. Also, sit down OutRun in the arcades. Nowadays is nothing like back then. I’m a shadow of myself gameplay wise and it’s not just because of the lag. Just too much responsibility to really lose myself in any game to that extent and you really can’t replace the innocence, imagination, sharp reflexes and eyesight of a child, not to mention available free time!

I’m really glad I could still appreciate so many aspects of what made these games truly special even till this day though. Things like the graphics/artwork, gameplay, design, sound/music. Those things can never get old for me and each time my CRT Shader Preset gets closer to what I imagined it adds a little more to a truly wonderful experience.

What do you think of those 3 Shoot 'em ups I just called? Have you experienced them yet?

Another gem that I mastered back in the day was GunSmoke for NES. I’m still relatively good at that. I just love how so many great games back in the day we’re relatively, short, intense and straight to the point!

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Just updated my new default and GBA-GBI presets to be ‘colour accurate’ rather than ‘mask accurate’ as being mask accurate really does break the colours on my display and doesn’t lead to any, significant at least, break down in the mask. In fact I’d go as far as saying it doesn’t seem to break the mask at all.

The close up photos of my display above seem to confirm this too - there is no cyan/magenta/yellow peeping through on my photos (I think).

This is confusing me a lot!

Am I just not seeing the problems because my camera isnt good enough? Is my LCD display just different to the way OLED’s show HDR colour? Can we get rid of this mask accurate/colour accurate option in favour of a solution that does both?

Thoughts welcome.

Anyway here are photos of an old classic with my colour accurate ‘default’ preset:

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I think I’ve seen some yellow in at least one of your screenshots in the past. I think it could have more to do with the camera focus. I see you use Auto focus a lot when taking screenshots. You might want to practice with manual and see.

I don’t know if it’s the same thing we’re talking about here but I’ve observed some distinct yellow almost like a yellow phosphor (next to the green I think) depending on how near my camera was to the screen when trying to focus my screenshots using fixed (manual) focus.

Just a slight movement toward or away from the screen and everything looked like proper RGB again.

My vote is to leave the option in if at least some users are reporting that it benefits them. Just learning from the example of the new RWBG option for OLED TVs we know for a fact that not all displays are created equal and flexibility is a good thing.

All of these screenshots look lovely by the way but do remember that not all users have been able to get this type of experience by simply following the setup instructions and loading one of your presets.

I haven’t even gotten around to trying some of these new options and settings yet, it would be a shame to see them go before I do.

Just sharing an example of the yellow peeping through and I can also observe the red and blue blending to create purple. Another observation is that the phosphors are slightly out of focus.

This is something that can be easily observed and mitigated if using manual focus.

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i think to be able to tell, we need to have shots that are close enough and focused to see the physical pixels rather than the simulated phosphors. That is, at the beginning of the thread, we needed to add some blur to hide the physical pixel structure, and we need to get back to that to detect whether the mask is softening (not necessarily a problem, IMO, to be clear).

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If you have in the close up front on shots I’d be interested to know which ones ( most are in the first post). Also all of those are taken with manual focus. It’s only latterly did I move to Auto as I found it pretty much always gave better results.

Yeah I wasnt proposing breaking it for OLED users it’s just there seems to be something a skew whiff at the moment and there maybe a solution that exists that works perfectly on both types of display (maybe not though).

It seems as if switching to a HDR swapchain may have ramifications in how colours are interpreted by the display as in although green rec. 709 is yellowey green on rec.2020 maybe the display interprets that as a pure green and hence there is no breaking of masks.

Maybe on LG OLEDs there is some amount of HDR post processing going on that breaks our specific use case. Maybe my screen is just broken in displaying HDR content and incorrectly displays it as pure green.

All not sure and I need to do more experiments on my screen.

As for the presets not working for people apart from a few issues around the mask on OLEDs and the grey ramp issue when looking in detail which have been resolved, the vast majority of people either didn’t have HDR working properly or were trying to use this with chroma compression. I’m not sure I heard of anything outside that group. It’s also going to biased towards people with issues. I don’t know - Id like to hear from people if they are still experiencing issues on a full chroma HDR setup.

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Yes these shots are artistic shots and are purposefully out of focus in parts and hence show the rainbows. I should have been specific about talking about the fully front on ones. Ive only been doing these fun shots in the last few weeks so there should be plenty of photos that are fully in focus.

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Yeah I should’ve been specific about avoiding these artistic shots for reference. The ones in the first post of the thread should be better references.

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Do note that I wasn’t attempting to say that there was anything bad about the shots being slighty out of focus. Just pointing out that the “yellow peeping through” that I was talking about was also associated with the image being slightly out of focus. I was trying to establish whether we were talking about the same “yellow peeping through” phenomenon, i.e. if it was the “rainbow” effect from the camera not being in focus or something that might have come from the weird OLED subpixels and with HDR turned on.

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No no sorry Cyber I should been a bit more specific about the photos I was talking about for reference. As I say I think all (most) of the front on ones should be in good focus to be able to see the sub pixels - in the original view i.e if you click on them in Discourse I mean.

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You’re making me nervous. My experience is totally the opposite from yours. Please keep mask accurate as it is the only color correct one for me! :slight_smile:

Maybe its because we are using very different setups: you’re using HDR (rec.2020) and I’m using the shader in SDR DCI-P3 (91% coverage of spec according to RTINGS)

Other things to consider:

  • Is the system gamma (curve) on your CRT identical to the system gamma (curve) of your LCD+shader output?
  • Does your CRT have sRGB color primaries or EBU color primaries or Sony color primaries?
  • Are the phosphors (color primaries) on your CRT accurate to their spec or slightly worn out over the years?
  • How accurate is the color gamut mapping: does your LED have good color gamut (volume) coverage of Rec.2020? Is there clipping of colors?
  • Is the white point of your CRT exactly D65 or something different? Is your LCD+shader output having the same whitepoint?

I’m stating the obvious for you probably but note that any of the above single differences can result in subtle but noticable color shift, let alone when adding them up. It could be that when the above align perfectly between the CRT and the LED+shader output that mask accurate is the one that is colour accurate.

It’s possible to get scientific answers to the above I think, but it requires a measurement device. An XRite i1 Display color calibrator or similar can do the measurement job as with it you can get the scientific data on your monitor, like the color primaries, the gamma curve and the white point. The harder part is probably to connect your PC to your CRT such that you can do the same measurements on it.

Retroarch has native support for CRT through CRT Switchres that is based on running a Linux machine (it can do native 15Khz support via modeline editing) or a Windows PC with CRT Emudriver. Another option could be DP->VGA dongle with ToastyX’s Custom Resolution Utility. This allows for custom modelines on Windows like on Linux. Soldering a VGA to SCART cable in the right way may be another challenge. Probably a HUGE rabbithole so probably not something to get yourself into without a lot of time on your hands… :smiley:

Anyway before this gets lost: please keep the mask accurate option in there as it is, and not fudge around with as all I know is that I’ve been a very happy camper ever since you put it in there!

Apart from some minor nice to have features (interlace support like guest-advanced has it) it seems Sony Megatron is pretty much perfect as it is :ok_hand:

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Yes don’t worry I’m not going to break things! I’m just wondering whether there is a solution that fixes both when I fully understand what is actually going on with my display.

So you said you just use the SDR version? As far as I remember the mask accurate/colour accurate doesn’t work for SDR. Hmm actually as I write this maybe it does for DCI-P3. But I think that colour space is broken in Retroarch as we don’t set a DCI-P3 swapchain. We’d need to add that support for it to really properly work like rec.2020 does. Hmm maybe this is part of problem?

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Yes I’m using it in DCI-P3.

I also wondered about the swapchain setting. From what I’m observing it doesn’t matter if you have HDR=OFF in Windows, then the monitor is always in its native color space which is DCI-P3 for my monitor (very very saturated red for example).

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Yeah I would agree, I had this same experience on my LG monitor using hdr (its hdr400), the overall color of the color accurate looked off, and mask accurate looked correct.

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Yeah I’m not sure we’re in true DCI-P3 space . I think instead in its in some quasi rec.709/DCI-P3 space as the proper gamma space for DCI-P3 are values in a higher range 10bit space like 32bit HDR. Kind of a poor man’s HDR that works in Windows non HDR mode. The only thing is that directx swapchain colour spaces don’t seem to directly support this at least not the 2.6 gamma curve.

See here for supported spaces:

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Yeah as I say I’m not going to remove anything if it breaks things BUT I’m trying to figure out what is going on here. Why does my display look very broken with mask accurate and then other displays look very broken with colour accurate. This isn’t making a lot of sense to me. There seems to be a fundamental difference in the way HDR content is being displayed or a bug in the swapchain code not telling the display how to display the swapchain correctly. This latter theory if right and being fixed where we might be able to remove the mask accurate/colour accurate option.

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Yeah that would be great if possible

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