Please show off what crt shaders can do!

Here is Z-Fast combined with pass2 from gtu-v50 just to blur the image.

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That looks decent with that particular content and gtu is a nice older shader. However, anything sprite-based will have overly blurred high-contrast edges, which can have a bad effect on the artwork. Details like small text, small icons, drop shadows, etc will also be overly blurred with such settings. On a (well-maintained) CRT, high-contrast edges remain nice and sharp. That’s why you need something like guest-dr-venom’s subtractive sharpening. CRT-royale has bicubic sharpening which does something similar (they might actually be the same thing, not sure tbh).

@hunterk can bicubic-sharp be ported to glsl and slang, and can parameters be added to adjust the level of sharpening?

Edit: here are some examples illustrating what I’m talking about.

horizontal sharpness 3.00, subtractive sharpness 1.00

horizontal sharpness 3.00, subtractive sharpness 0.00

horizontal sharpness 3.00, subtractive sharpness 1.00

horizontal sharpness 3.00, subtractive sharpness 0.00

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Sure, done. Lower Bs and higher Cs make it sharper at the cost of ringing. 0.333 is the default for both (the Mitchel-Netravali coefficients, whatever that means).

bicubic-sharp is B = 0.1 and C = 0.5

bicubic-sharper is B = 0.0 and C = 0.75

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I guess we don’t actually need to add bicubic sharpening to zfast? It didn’t seem to do anything, after all. :sweat_smile: The blur/scaling in zfast already does a decent job of keeping high-contrast edges sharp.

Something about the blurring/scaling in zfast doesn’t sit right with me, though. It seems like zfast is blurring using the regular sRGB color space instead of blurring in linear gamma sRGB color space (I might have this backwards), so you get weird-looking stuff like the text and the border around Link’s shield in the below example.

Zfast-crt, horizontal blur 1.00

Guest-dr-venom, custom settings

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Some N64 and DS pics using Kurozumi’s Guest-Dr-Venom preset!

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Kurozumi’s preset has some soft clipping and a lot of banding, and contrast seems to be pretty lacking. Compare these two images.

my guest-dr-venom settings.

How does one contribute a preset, anyway? @hunterk

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that’s a bit of an apples-to-oranges comparison, though, to be fair :stuck_out_tongue: He’s going for the wide, black gaps rather than maximizing dynamic range. Ideally, we’d be able to do both, but we’re limited as you well know.

Just make a PR on github and put it in the “presets” directory. Yours would be good to have in there.

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I really-really like your preset, that’s what my own GBA preset (pics posted previously) is based on.

But, I can’t use your preset outside of RA in ReShade as it requires @Dogway’s Grade shader (which is not available for ReShade at the moment). Without it the preset just doesn’t look right.

I’d love it if you can post a version of your Guest-Dr-Venom preset without Grade in it.

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True, you just can’t have both until we have access to much brighter displays. Now I’m working on something a bit more BVM-like, maximizing the black gaps while minimizing clipping and eliminating the banding (which I think was caused by the mask being used). I increased the beam shape high parameter to 45.00 by increasing the maximum range for the parameter, among other things. Here’s a preview. It should go without saying that the LCD backlight should be maxed out for this (as it should be for the Kurozumi preset as well, and for all my presets). Feedback is welcome.

Thanks for the info! I’ll upload my dynamic preset and this new one after it’s more or less finalized.

@DevilSingh

Glad you like it, and I like those GBA pics but they might be a tad washed out, at least on my display. Admittedly, I’m not familiar with those games and that just might be how they’re supposed to look. Are you using grade with the GBA preset? The sigmoidal gamma in grade is really great for expanding the dynamic range (I just leave it at the default of 0.50). Also, if you raise bright boost beyond a certain point it’ll wash out the colors and eventually result in clipping.

To remove grade from the preset, you can just replace it with stock.slang.

I’ll upload some presets once this new BVM preset is dialed in.

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Of course, with a bit more clipping we can make this even brighter. Now it’s starting to look pretty close to Kurozumi’s preset :stuck_out_tongue: Need to throw a few different games/systems at this and play around with it some more.

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This still isn’t finished, but I think I’ve made some decent progress. I expanded the ranges for beam shape low and beam shape high; expanding the range for beam shape high helped a lot (beam shape low, not so much). If you’re willing to do crazy things with gamma, you can get some very thick gaps while still maintaining an adequately bright image and decent saturation and contrast. There’s still some very slight localized bloom with the very brightest colors, but I think this is starting to get pretty damn close to some shots I’ve seen of BVMs. Color temp and such could probably use an adjustment, but I’m not focusing on that right now. I’m going to try expanding the range for gamma input/output, next.

Images must be viewed at full size and with the LCD backlight at 100%.

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Firstly, I should note that those GBA pics I posted before are from the standalone version of mGBA with ReShade. Should have mentioned that when I posted them, lol!

Here’s how your preset looks like with GBA games in RA.

No shaders :

Your preset :

Your preset (with no Grade) :

My GBA preset :

I’ve also tried your preset in ReShade (no Grade obviously) with some PC games and I get the same result as here - overblown whites and bloom, too much saturation (this is probably down to the differences in our displays).

This is the reason I requested a Grade-less version of your preset.

(No idea how those shots look on your end though.)

P.S. - Your BVM preset shots look great. Still very saturated on my display (same as above). Don’t know if its any help, but my monitor is a DELL IPS panel with 2.2 gamma (not that it matters as I use the default 2.4 input/output gamma in Guest-Dr-Venom with no problems)!

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Some Guest-Dr-Venom ReShade test screenshots I took yesterday!

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Yeah, something is definitely wrong there. Are you using the preset posted here?

As for the over saturation with the new preset, yeah. Still tweaking it, thanks for the feedback.

How is this looking? Remember to adjust your backlight to 100% and view the images at original size; downscaling does all kinds of horrible things to the image. I also haven’t done any grade adjustments, yet.

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Yes, I’m using the up-to-date preset in the first post from there.

The new BVM screens look great.

Weird. I think this might have something to do with the scale, I use 5x scale (vertical) for just about everything. Can you try that and see if it’s an improvement? As for the colors, it’s probably related to color temp. I can’t remember what I have the color temp set to in the preset, but maybe try a lower temp like 6505K or 5505K and see if that helps.

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This is more or less done, just hoping to get some feedback before I go ahead and upload.

First shot is with minimal bloom, rolling the highs / introducing some soft clipping at the high end. Basically, the gaps over the brightest colors are as dark as possible, but you sacrifice some dynamic range.

Second shot, the gaps over the brightest colors are a bit reduced but dynamic range is better. Personally, I think this still looks very BVM-like and is a nicer image, overall. Trying to keep the gaps over the very brightest shades 100% black loses too much dynamic range IMO, and BVMs are known for having insane contrast ratios.

Usual disclaimer applies; increase LCD backlight to 100% and view images at their original size.

less bloom, less DR:

more bloom, more DR:

edit: a few thoughts.

  1. This gives me some ideas for further improving the DR in my currently existing shadow mask preset.

  2. I’m tempted to remove the mask altogether, since the TVL of a BVM is pretty much on par with a 1080p LCD, and these settings are intended for 1080p. These settings may not look as intended with higher resolutions/scales, as per @DevilSingh’s GBA examples. The mask does help to reduce clipping at the very high end, though. So maybe it’s best left as-is…?

  3. I had to expand the ranges for the beam shape parameters to 1.00 - 100.00 for this to work, so I don’t think a normal preset will work. I’ll have to either include instructions for increasing the beam shape parameter range (pretty easy stuff), or maybe @guest.r would be kind enough to change the ranges. What do you think, @guest.r?

  4. I haven’t done much with grade, I just set all the color palette stuff to sRGB and color temp to 5505K. Any suggestions here would be welcome. Of course, all of this stuff can be tuned to preference and/or display conditions using the parameters.

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I need my bad games to look as bad a I remember. I have a new favorite ugly CRT shader. It has scrolling scan lines, convergence, and few other artifacts to make it all nice and fuzzy. The first screenshot is no shader, than new_pixie, and finally my adjusted version of the mame_hlsl in the crt folder.

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Somewhere between the Mame shot and the pixie shot would be pretty sweet tbh.

The shots look good though.

Seems like your preset works perfectly with SNES games. And 6505K white point temp looks the best on my display.

Native 1080p Res :

5x integer scale :

After testing it with SNES games I thought maybe the GBA color palette was messing with the shader. But, even adding the GBA-Color shader (which simulates GBA’s LCD screen) doesn’t seem to help.

I’ll stick to my own preset for GBA games for the time I think.

P.S. - I prefer the 2nd BVM pic. Nice work!

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