This is great work @rafan! What display do you use?
Will you consider packaging a preset pack or at least posting all of your modified preset code as you go along or when you go through all the Sony Megatron Color Video Monitor presets that you use. This would be a great help to users like myself who don’t have as much knowledge and understanding of how colour systems and calibration work!
Brilliant work in improving this awesome shader!
Hi @cyber - that’s my point you can’t make a preset for this with HDR. It’s different for everybody’s display (assuming they have different displays of course).
SDR is different in that a lot of people’s displays are capable of the full rec.709 standard.
That’s why I asked @rafan what display he uses. His settings won’t work for everyone but they just might happen to work for some with the same or similar displays. They might even work better than the defaults on different displays for some users.
Maybe in time others might share their calibrated presets as well and eventually what started off as a couple presets might someday grow into a large database.
When more and more users start diving in and figuring stuff out about the shader and how to improve the experience on their own then share their presets and findings that’s what will create and generate more buzz and excitement around the shader as the community of users start to grow.
I don’t know, I think a calibration wizard is the way to go for this. A thousand and one presets would surely just confuse users. At least this is how games deal with this problem.
Hey @Cyber
It’s a Samsung Odyssey G7. It’s a very nice 1440p monitor. I think somewhere down the road I would want to “upgrade” it to a bright 4K monitor though, as it would be very neat to comfortably use slotmask and lower TVL settings in the shader for an even more close CRT experience. With my current monitor only TVL1000 setting is up there for enough brightness.
In that regard I’m also curious about OLED, since you own one, does it bring a more CRT-like smooth(er) motion with fast scrolling stuff in your opinion? How would it compare to a good LED motion wise?
Hmmm…my OLED is “only” a 60Hz one. I’ve recently switched between a 4K LED and my OLED and I couldn’t wait to get back to my OLED mainly for the contrast, the better black levels and lack of blooming.
I don’t have any issues with motion clarity on either. I don’t always try to nitpick when I’m immersed in a game though. I have noticed that I couldn’t see the mask pattern clearly in the backgrounds during fast moving or scrolling sections of games. On objects like the main characters (when stationary) or status bars or even static backgrounds in a boss arena or title screen for example it’s not an issue. In general it isn’t an issue at all at least for me as it’s only something I notice if I’m looking for it. Same goes for judder.
I would assume that something that can do BFI properly and still have enough brightness left over so you can see everything properly might be a sight to behold but for me who only has distant memories of CRTs to compare its more than good enough even without.
On my OLED TV, I notice trails from fast moving bright objects on a dark background quite frequently even without tricks like afterglow in my presets.
When I switched back my biggest disappointment was realizing that most of the mask patterns that I used that worked quite well on my LED TV looked really off, incorrect and downright horrible on my OLED TV.
That motivated me to investigate this further and further because others had written off OLED TVs and good colour mask emulation which I wasn’t satisfied with at all and I eventually stumbled upon specific mask patterns that actually worked much better (at least well enough) with OLED TVs.
So no matter which display technology you choose, there’s always going to be some sort of tradeoff.
I think a good 4K miniLED TV might be a good compromise between the two competing technologies.
Specifically one of the new TCLs which has a relatively conservative dimming algorithm which handles difficult for miniLED scenes like starfields very well.
The photo was to demonstrate the improvement to the mask on my OLED, but the overall image still had clipping/crush issues in the highlights and on similar colours unless using the JVC presets as described here:
However, using the new colour-accurate parameter, all these issues are gone unless pushing the paper-white too high. Everything looks correct with paper-white at around 550 (nits at 720). Thanks for the amazing update!
Fantastic great to hear! What model OLED are you using again?
It’s LGs latest 42 inch ( OLED42C2)
I’m loving the Megatron shader, been doing some more extensive testing with various cores and overal everything works great, but yes I did find one thing that could possibly be improved. Not a bug I think but more something feature related 
The bottom line is that interlaced content does not look right. For example there are many Playstation 1 games that mix low-res (320x240) with hi-res (640x240) and hi-res interlaced (640x480i) content, and this hi-res interlaced content does not look right.
I’ll explain a bit more thoroughly, hopefully it is something that you could look into.
I’m seeing two issues happening:
Interlaced content does not look right as scanlines dissappear completely.
What I would call “medium-res” (i.e. 640x240) is looking too sharp. I think this is because the shader “sharpness” setting is tweaked for low-res (320x240), but when a game switches to 640x240 in-game the horizontal filtering is not adjusted to this new resolution.
On issue 1 a bit of extra explanation may help. There are some cores that support real-time resolution switching just like the hardware did. Some cores that do this are for example the Mednafen PSX core, BlueMSX core, the Commodore Amiga PUAE core and some others.
As an example of the many oddbal resolutions that may occur here’s a video that lists all PS1 games that use interlaced as the base resolution - in the entire game - (he leaves out games that only occasionaly switch to interlace for title screens etc):
Playstation 1 ALL (?!) Interlaced (Hi-Res) Games
The resolution table that is mentioned in the readme “more” link below the video is interesting:
00:00 Intro
00:05 Hi-Res Mode?
00:35 Debunking 480i Myths
02:18 320x240
02:45 256x480
03:11 312x448
03:34 320x480
04:39 368x480
07:15 382x480
07:45 384x480
08:14 512x478
09:36 512x480
13:52 640x448
14:09 640x480
To not make this post too long and not knowing if you’re already familiar with the technicalities of CRT interlacing the summary is that for correct CRT interlacing simulation you need to weed out the odd and even lines fields from the emulator frames output and have the odd and even lines fields alternating at a slight offset from eachother.
Note that in a CRT the offset is about 0.5 lines. You and I know this is possible because it’s analog television and the phoshpors of the previous field have already died out when the half line offsetted other field is displayed. Rinse and repeat. Through persistence of vision the human eye and brain then sees a 480 tall picture. If you’re interested I could provide more info on CRT interlacing.
As an example this guy explains it nicely. It’s a simple explanation just using his hands and it’s for 1080p/1080i but the idea is the same for 480i CRT:
TV Explained: Progressive and Interlaced . The interesting part is from 3:34, at which the previous link starts.
I know guest.r has done a great job implementing interlacing into his advanced shader that’s virtuously indistinguishable from a real CRT. I’m hoping something similar could be achieved for the Megatron shader.
Possibly the de-interlacing.slang shader from HunterK in the misc folder could also provide some additional idea what’s happening, although this seems to be only for “normal” content and not directly applicable in a shader that has scanlines simulated etc…
I think this could really put the icing on the cake. As always thanks again for the superb Megatron!
Great investigation, thanks! Yes sure I’m guessing de-interlacing doesn’t work as I haven’t looked at it. I’ll definitely add to the to-do list.
My main focus at the moment with regards to CRT shaders at least, is to get TATE mode working for the d3d9, 10, 11 and 12 drivers. I’ve made some progress but there’s one more thing to fix before I can submit to GitHub. I hasten to add that’s nothing to do with the Sony Megatron shader but the drivers themselves.
I came across this page that tries to list all subpixel geometries that are used in-practice on modern screens, including phones. Not for any direct use, but since there’s been regular discussion on subpixel types I thought to flag it anyway:
Subpixel Zoo - A Catalog of Subpixel Geometry
Flagging this also to @nesguy and @Cyber for our resident subpixel gurus
Just got an HDMI cable so I can use RA on my LG OLED CX! Any suggested settings to use? I’ve tried messing around with the HDR settings, “peak luminance” and “paper white luminance” but the image is still very dark.
HDR is working, I just can’t seem to find proper settings.
@datjocko seems to have gotten pretty decent results. Maybe they can share some settings?
Or maybe even @Wilch?
Hi @e2zippo, hmm that’s interesting, as @cyber says some other users with that TV seem to be getting good/acceptable results - so there’s hope at least. If you use SDR is it even darker?
I have LG CX too and the HDR picture is bright and awesome on Megatron.
I’m using RetroArch on Xbox Series X where you can’t normally use HDR but there’s a workaround: if you go to ’All Settings’ and press ’1, 1, 1, 3, 1, 1, 1’ while the ’Picture Mode Settings’ text is highlighted, you can access the ’HMDI Signalling Override’ screen where you can force HDR on by selecting ’ST2084’ for ’EOTF’.
But yeah, Megatron is awesome! Can’t really use any other shader anymore. Hopefully the TATE support comes out soon, can’t wait to try this on some shmups.
“The photo was to demonstrate the improvement to the mask on my OLED, but the overall image still had clipping/crush issues in the highlights and on similar colours unless using the JVC presets as described here: However, using the new colour-accurate parameter, all these issues are gone unless pushing the paper-white too high. Everything looks correct with paper-white at around 550 (nits at 720). Thanks for the amazing update!”
using the new colour-accurate parameter What is this and how to I use it? I seem to be having clipping/crush issues as well
Another thing I’m wondering is what settings are you guys using on the TV? @Scarf @datjocko @Wilch
Specifically Dynamic Tone Mapping? On / Off / HGiG?
Hi @e2zippo make sure you’re up to date with Retroarch and then make sure you update your slang shaders. You do the latter by selecting a slang shader valid video driver - Vulkan/D3D12/D3D11 should all work - then go to the online updater option and ‘update slang-shaders’. Once you’ve got latest you should see an option in the shader parameters for ‘mask accurate/colour accurate’. Also you can choose a OLED sub element layout ‘RBG’ instead of ‘RGB’. Should work.
Hi @Scarf glad you’re liking the Megatron. So you should be able to play in TATE mode on the Vulkan driver - if you can use that (possibly not on an Xbox but PC definitely).
Here’s a few screenshots I’ve just taken - I have to say I bloody love it:
I’m all up to date. I just realized I’ve been doing stupid things. I’ve been trying to load the presets that come with @HyperspaceMadness Mega Bezel located in shaders\shaders_slang\bezel\Mega_Bezel\Presets\Base_CRT_Presets\Sony-Megatron\STD
They are all SDR, not HDR 
Tried some of the shaders in shaders\shaders_slang\hdr instead that are called HDR and they look way better. No I can properly check!
Thanks!
