111 posts were split to a new topic: CRT Squabblin’
Yeah, the way it seems to work (which is unfortunately very hard to express in code) is: the phosphorescence decays almost instantly on blue and green but the reds last longer and exhibit a long tail of up to a couple of seconds, depending on the phosphor material. If a given pixel is re-lit during that falloff period, anything greater than the current fading value completely overrides it (i.e., there’s no additive brightness from the previous decay). There will be some visible rolloff even on nonblack stuff, as long as it’s a brighter->darker transition, but due to the big-initial-drop-with-long-tail behavior, you’re never going to see it unless the darker pixel is very dark indeed.
I’m also not sure how/if different follow-on colors affect things (e.g., red decay followed by bright green) and/or chromatic aberration.
I agree that anything using thresholds looks bad the closer you are to that threshold, but I’m not sure that a better, more realistic method is feasible.
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This looks really good! I think it’ll be a great addition!!
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Thanks for the answer. I didn’t want to appear lazy or something…
I tried to search for these things before asking. But I didn’t use the search function. Just tried to manually read through this bigger thread.
I am thankful for your work on these shaders and the detailed answers, I’m just rather new to a more technical approach of using shaders…
Sadly the kurozumi-guest.slang preset doesn’t work anymore on my macbook air 2015. These days I use kurozumi-royale or your guest-venom version.
I did’t want criticize your default preset. Just curious.
I think I’ll just leave out the afterglow feature for now. I first want to get colors as right as possible, but I’m struggling to be satisfied.
Maybe another question: would you guys prefer to use the lut parameter, or the crt-color-profile for adjusting your color settings? I couldn’t get the saturation parameter to anything I wantrd. Is it advisable to crank scanline saturation up to 2 or do I have to bear artifacts in mind? Same for scanline-spike-removal?
So thanks for the work and this nice thread.
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I like the addition of the mask aperture trinitron style. But is it possible to know more about it? I tested the revision1 guest advanced… The mask had some strange things, like ssss and dollars as mask pattern… But with revision 2 everything is fine… 1/ was this due to my oled structure wrvb vs rvb? Or was it not intended to work this way? 2/ without bothering guest I wanted to know if he had a personal version with more settings? Because I saw a post where they were looking for 4k optimization, and lightened up the options for the users ease. But my question is if there is a guest advanced rev2 version with more settings? Just a question, why? Because I’m working on a shader preset that offered me 4 gammas to fine tune the colors contrast luminosity… The result is a bright image with good contrast. Example shader misc slang ( 4 gamma settings at different places)
game embedded gamma/ crt electron gamma/ simulated crt gamma /your display gamma
crt royal simulated crt gamma/your display gamma
So is it possible to have this versatility of gamma settings in guest advanced rev2? Or do you have your own shader that you reserve for yourself because you think it would be difficult for the end user? Because it makes a difference to me all the way through the image process, with the integration of mask and ensure a bright and clear image, not dark and dull. Again bravo for the shader, because I use it now, must redo the work from scratch, 1 month of work lost… No big deal, for now I’m having trouble matching the color brightness of guest advanced v2 to the basic misc slang.p preset (because less gamma adjustment) The preset I used available to all at retroarch I post here that you can see what I am talking about gamma… My preset genesis.i don’t remember exactly its name at retroarch but this is the one… Preset for 4k slot mask ( instead of aperture grill so I start from scratch with guest advanced v2) Custo 8x9 is for the correct format without artifact on 4k oled tv ( preset that has a trinitron border so image framed ).
https://drive.google.com/file/d/1oOOX7uG59pKejCNN8iXfBqfOX4_i-bnv/view?usp=sharing
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I’m not sure if you have already tried this out or not, but some OLEDs have a Peak Brightness setting which when turned on uses the white sub pixel and when off does not.
There was some discussion a while ago where it seemed that turning the white subpixel off might result in better per mask display.
I haven’t tried this myself on an OLED though so this may just be theory… 
Maybe @c9f5fdda06 might have some thoughts on this though.
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Indeed read that somewhere… But my preset uses bfi (black frame insertion) And that my preset takes into account the 40℅ of luminosity loss… And that for that to have 4 gamma allows to adjust more easily the rendering, and that the final image Is bright and contrasted. Thanks
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A good question is for which calculations a specific gamma value is required. In fact you have more gamma options at hand, including gamma correct and mask gamma.
Colorspace gamma is hard coded by specification.
The NTSC version also includes scanline gamma. Unfortunately each customization slows the shader down and adds more parameters, which i try to avoid.
So to speak if you want more custom gamma, there should be a context reason with explanation for it.
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Interestingly, the latest Retroarch update that supports HDR allows me to take advantage of it but Guest and HSM shaders don’t play nice with DirectX11, 12. From my experience it seems that persistence is the main culprit. Hopefully we can get support for Vulkan HDR in the future!
Unfortunately, on the LG C9, I have to use something other than game mode to manually enable the white pixel for non HDR modes. This introduces lag 
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Unfortunately, it doesn’t help with subpixel masks. Black and white masks are your best option with OLEDs, I think.
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I have a panasonic oled ez950 . I don’t have the option of white pixel enabled or not. And I have a shader preset where I am at 70 or 80 in maximum contrast in rec709…and I use the bfi which reduces 40% of luminosity, ( wrvb because the oled slabs are made by lg and panasonic uses that…) The hdr would be brighter for me than my sony kvb crt at max contrast…
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what i see is identical to you nesguy, on my oled wrvb no? for me it’s identical same phosphors, same rendering but in 4k can be more accurate, but i’m not going to plug my plasma panasonic g20 1080p to compare. my question is when you talk about magenta mask, or black and white mask, I don’t see any magenta mask, did you open the mask in photoshop to see more closely maybe? Always a pleasure to share with you. CRT SHADER GUEST ADVANCED REV2 ( trinitron aperture grill oled4k wrvb)
thank you guest for adding the mask you are a killer
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Some very quick, dirty, off axis, far from perfect, cell phone camera photos of my Arcade - Sharp shader preset showing the mask pattern on a 4K OLED TV. @Brainbin74 Somehow my most recent screenshot uploads using imgur appear much darker than the shader presets look in actuality. I didn’t use imgur for these though.
Of course in actual use the presets look much better to the eye than these bad camera shots but they can still be used to illustrate the pattern of the mask and scanlines.
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What I see is as good as what I see at home. The oled wrvb displays mask and scanline without any problem. I saw a post somewhere from hunterk that says so ( it doesn’t pose a poblem) So we share, that the users of oled is reassured… I like the rendering of your preset in photos. Yes I know that the photos do not do justice to reality. But anyway my oled is calibrated at delta 1 max, and that users will look at that behind their screen, if they are not calibrated themselves? So it’s just for information and to see the aperture in action. Cool my friend, you’re having fun, it’s a nice rendering.
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I say it every time, but I think I have tweaked it to where I want. On an ageing 42’’ LCD TV at 6ft away, it looks pretty good. The only thing I’m still slightly unsure of is the convergence. I might do away with that.
Hi, you are using a shader that is accurate in 4/3 crt emulation, so your final image is stretched to 16/9. I’m a frank and honest person, so I’ll tell you what I think. I think that even without shader in 4/3 you will be better… Without filter. That’s human divesity, choice, and.opinions… But I would never bother to put a shader that has a mask or something because most of them are not designed for that, 90% of shaders work well in integer scale and 4/3… In 16/9 I only see artifacts, oval cartwheels. Otherwise well the image is correct in gamma, contrast…
I don’t see a convergence problem here. I’m looking at zelda logo trademark, ® if you had any.convergence changes… I would see either red outdated left or right or green or blue. The convergence is just to simulate a malfunction of tv crt…badly adjusted… Either you like bad tvs, and you use convergence, or you emulate a trinitron crt which has no such problem. Here you go my friend, have a good game.
I don’t think that the shader math depends on 4:3 ratio at all. I have used Guest Advance at a dozen different aspects,. (Some consoles and computers didn’t use the whole screen and the aspect was not exactly 4:3.)
For example PSP and PS2 look great in widescreen with Guest.
@brad86 Nice work!
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Hi my friend, don’t worry I’m still thinking about making my crt photos so you can make a border overlay, recharge my battery yesterday from the camera, this will be done.
To answer that’s why I say 90% of shaders, what I know is that shaders capable of not making artifacts in the middle of the screen are rare, it’s a fact. I take crt royale? It’s made to simulate a pvm bvm, in full screen you don’t have the scanline just falling off…that’s a fact, and 90% of shaders do that… You should make a list of shaders that can do that. But out of 60 different shaders only 3 have this capability, I think crt lottes does it well, and guest advanced??? All the rest will be only artifact in movement and scanline which falls badly… Its screen is 1080p 1920x1080 the snes is 256240 overscan, or 256224… The horizontal and vertical resolution must be an integer multiple to look right, on 90% of shaders as I said above it will not pass, but I respect everyone’s choice, just giving my opinion and information. Have a good game.
Hunterk says here all shaders will look better in full scale. This is not from me, but from the shader creators who explain that this is calculated like this mathematically…
To conclude, what would be the use of the integer scale option in retroarch if all the shaders were perfect in full screen on any TV…this option would be useless, just to put core provided 4/3… And all shader would look perfect. I share truth and facts here that allow users to understand facts. And I said it above, but you say that it looks good to you in full screen with guest? So if it looks good to you, that’s fine, but it doesn’t mean that it’s perfect. And the shader creator is trying to be accurate…otherwise you put an overlay with scanlines… Not precise but will have the same result, which will be a rendering that is not crt, but a rendering that pleases the user, I respect his choice, but if you post pictures, it’s to have opinions no? If not, if it’s perfect for the user, then other people’s opinions don’t matter. Good game friends