New sonkun crt guest advanced presets thread

Notice the other little changes too, as without them the threshold effect doesn’t have big effect. This is because the images is heavily modified before it gets to scalefx. And compare the bottom two images on Link, the variation looks a bit more rainbow-ish and the numbers (zero in example) are more round.

But who knows what side effects this has. I am not experienced enough to make suggestions with confidence. Just wanted bring up this to discussion. Just happen to play with the settings for this shader. I am not the target audience for this preset anyway, because I like your “regular” set of shaders a lot and the standalone scalefx. So there is no need for rush from my perspective. :slight_smile:

Yeah I see the little differences when looking a bit closer, nice touches.

Ah ok no problem, I’ll just leave it the way it is then and if a few people come in saying they want the default scalefx look I’ll revert it back.

As far as I know, any of those consoles: NES, SNES, Genesis always came up with RF switch by default. Yet, I barely have found any preset that may have this representation through shaders. Noise alone approaches great to this bad video signal looking with interference but it’s still not explored well enough with the types of interference you can get on a TV. Even flat screens look old (and so then more accurate to that era looking) when it’s wired to RF Switch… I still do have a 30+ years old functional NES and the noise definetely brings up some old looking to flat screens if this cable is damaged to an extent.


Maybe if you can you can take a few photos of it in action? Could be nice to use as a reference if nothing else.

New Version Release (03/04/2023)

Changes Made

  • Uses guests latest version ( 2023-02-25-r1) shader update.

  • Welcoming to the pack are brand new Aperture Grille and Shadow Mask presets to go along with Slot Mask, now you can choose from the 3 common crt mask types to have fun with and do your retro gaming with!

Shadow Mask:

Aperture Grille:

  • Added in a new (old) preset back into the mix, I call it “composite-ntsc-2-phase-megadrive-rainbows”. As some of you know the Genesis produced a certain rainbow effect, this preset is made to give off that accurate rainbow dithering look. So now you have two ways to get your dithering through composite either with the standard composite 2-phase ntsc preset:

Or the megadrive composite 2-phase ntsc preset:

Bringing the total count from 48 to now 56 presets to choose from. Title of the thread will no longer have the word “slot mask” in it since now 2 other crt masks have joined the pack.

  • I’ve created two different types of presets, one for curved screen presets and one for flat screens. I’ve gotten asked a few times on how to turn the curvature off so to make things easier for everyone you can now choose right off the bat if you want the curved screen:

or flat screen look:

Curved and flat screen presets both have their own folders, the more options the better right?

Grab this newest update in the first post.


I’m seeing “runt” scanlines in your Shadow Mask screenshots. So far I’ve managed to eliminate those by increasing the integer scale percentage/offset.

You can take a look here if you would like to learn more.

I tried with this little camera but may not look so good/convincing to be honest. It looks like video signal is permanently trembling. I dont know how to explain it. The signal is not static like at least composite video could ever provide. But the rainbow artifacts are present as well.

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Anything involving integer scaling I’ll pass on, I don’t use any form of that in my presets. If there’s a bit of “runt” scanlines so be it, everything can’t be perfect. Thanks anyway. You game on a 1440p display I believe so I’m not even sure what you’re seeing on your screen since I think I got the mask shift number wrong for 1440p displays. I know that number needs to be on 7.50 for 4k since I tested that myself.

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Cool I’ll check those out when I get a chance, thanks for the links.

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The use of Integer Scaling may not be the only solution. I just mentioned that because it’s what I did and I probably had it on already in those presets probably because of the artifacts I have noticed in SNES games using smaller viewport sizes. So you might be able to eliminate or reduce them using Non-Integer scale as well.

I use a 4K screen and I’m judging based on the screenshots you posted in your release using my phone.

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What’s the reason for not using integer scaling? It’s quite possible to maintain a 4:3 ratio or whatever while using integer scaling, if that’s what’s holding you back.

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I like to get the full 4:3 aspect ratio. I know that within the guest shader there’s that integer scaling setting but I simply don’t like cropped images or images where some of the image is cut off. I dealt with enough of that in the 90’s on real crts. The moire and “runt” scanlines as cyber calls it isn’t a deal breaker to me, haven’t seen anyone that’s downloaded my presets come in complaining about it so it’s not a big deal. It’s part of the non integer scaling territory and I accept it.

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Ah ok. In any case I swapped out a quick update using the right settings for shadow mask on 4k at least, I’m sure when guest replies he’ll give me the right number to use for 1440p displays like he did for 1080p.

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Those “different” looking scanlines appear even when using Integer Scaling. It seems as though this particular artifact is unique to Shadow Masks but I can understand that you’re not too bothered by them.

There is no 1 “right” setting. It all depends on what you’re trying to achieve as well as your particular scaling settings as well as resolution.

I meant right as in making sure the rgb phosphors follow the same pattern as in this pic:


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Hey I just setup a old crt computer monitor the other day. Am I able to edit the shaders so that they are in at 1024 x 768? Amazing work btw.

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Hello and welcome to the forum. Your resolution falls in the 720p category I believe, I’m not even sure if the guest shader works properly in resolutions below 1080p, I can’t confirm that information though, maybe the creator of this shader @guest.r can give you a better answer. Thank you for the kind words, my latest update brought things up to the next level.


You are basically limited to 2 pixel wide masks or no mask at all on such displays, otherwise you have a very coarse and low TVL look. That can be ok for a small display too though. Also, these low resolutions are worse when it comes to non-integer scaling.


hey, just wanted to thank you for sharing your wonderful presets! guest’s shaders are fantastic but very complex, so I’m happy to have someone else fiddle and fine tune the settings to get a nice alternative to the default, especially with things like glow and sharpness which I find difficult to tune in just right. your presets give me a good starting point to make further adjustments to my liking.

it’s funny that your new update contains both aperture mask variants and flat screen variants as this those were both the two biggest changes to your presets I made myself this past week! looking forward to trying yours out.

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Thanks for the info I have tried the 1080p shaders but the scanlines are too big for the 1024 x 768 resolution. I have looked around online and found something on reddit saying set my resolution to 240p but I don’t want to do that because I want to use my monitor as a 2nd monitor for pc use. I think it would be a nice simple solution for people with real crt computer monitors to have these shaders to work properly at 1024 x 768.

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