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RetroArch Additions Shaders
#512

If it’s the scanlines themselves that are visible over black, that can only be the result of the black level being set too high. Of course it’s personal preference etc etc but with the black level being higher you’re necessarily reducing the dynamic range / contrast ratio…

It’s contrast ratio / dynamic range where LCDs fail the hardest at emulating a CRT, IMO. My eyes keep craving more and more contrast and saturation until I eventually snap and turn off all the mask effects, which also doesn’t look right because it’s too blurry.

However, I recently discovered that mask 8 and the gdv slotmask by themselves are very good at preserving contrast and saturation compared to the rest. With the other masks you kind of just have to embrace the clipping if you don’t want an overly dim, dull image.

Super Metroid (JU) !-201205-155548
Super Metroid (JU) !-201205-1555481494×1120 979 KB
Super Metroid (JU) !-201205-155542
Super Metroid (JU) !-201205-1555421494×1120 1.07 MB

outrun-201205-160810
outrun-201205-1608101494×1120 621 KB

outrun-201205-160817
outrun-201205-1608171494×1120 713 KB

3 Likes
#513

I think the primary issue in this discussion is we are wanting different things, your leaning hard towards 1:1 perfect emulation and at least me, is leaning for quality looking and the ability to add the “shitty” defects (deconvergence, scanlines over black, static/grain, mask over bloom halos).

3 Likes
#514

Well yeah we have different preferences, but I’m not sure why this is an issue…?

For me at least, many of the effects lead to the uncanny valley sort of thing that hunterk mentioned. I have enough experience with how these things look on an actual CRT that I can pretty much immediately tell when there isn’t enough contrast, saturation, etc, and I do prioritize that above everything else because it’s essential to the whole CRT phosphor glow thing; IMO that’s what makes an image on a CRT look amazing. I’m also considering how these effects look when actually playing a game vs. a screenshot.

I guess I don’t really have nostalgia for low quality TVs, I have nostalgia for CRT phosphor glow and contrast ratio. Even a crappy Walmart CRT TV had a better contrast ratio than most modern displays.

CRTs have contrast ratios of at least 150,000:1. The worst CRTs have thirty times better contrast than the best VA LCDs and 150 times better contrast than the worst TN LCDs. TN LCDs have up to about 1000:1, depending on the monitor. IPS LCDs have up to about 2000:1, depending on the monitor. VA LCDs have about up to 5,000:1, depending on the monitor.

https://www.reddit.com/r/GloriousCRTMasterRace/wiki/guide#wiki_better_contrast_ratio

3 Likes
#515

@guest.r

I just started playing with the filtering options and I can already see the advantages vs. subtractive sharpening.

What settings do you recommend for sharp high-contrast edges but smooth elsewhere (the bicubic look)?

first attempt:

Super Metroid (JU) !-201205-173528
Super Metroid (JU) !-201205-1735281494×1120 787 KB

2 Likes
#516

From my experience such a look starts at horizontal sharpness below 4.0 and is usable to about 2.4. Good spot is 2.8 -3.2. Substractive sharpness 1.0 is special, other is convenience or preference.

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#517

I know you just mentioned not being nostalgic for crappy images, but I like (and recommend trying) NTSC encoding for Super Metroid. A lot of the backgrounds benefit from it greatly.

7 Likes
#518

Yeah that’s the kind of thing I’d be more inclined to try, where it benefits the image. I’ll give this a try.

1 Like
#519

My issue is how dismissive you’re of anything that doesn’t conform with your vision. Like I’m fine with you having opinions that you also tend to back up with technical analysis, I just don’t like how dismissive you come off.

I’m perfectly fine with others not agreeing with how I like the image to look. I’ve never dismissed your razor sharp presets you’ve done, tried a majority of them.

1 Like
#520

Where do I come off as dismissive? Sorry if it came across that way. I thought I was just providing clarification. :man_shrugging:

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#521

It’s kinda in your wording I guess, because in our context using the word nostalgia in the manner you do, it comes off as dismissive.

You’re fine, maybe I’m just being butthurt.

1 Like
#522

Uh yeah I didn’t mean nostalgic in a bad way, I did after all say that I was nostalgic for CRT phosphor glow and contrast ratio; that’s the most striking thing about images on a CRT to me and it’s pretty essential to the intended look IMO.

I don’t think my presets are razor-sharp compared to a CRT using RGB or S-video or a decent comb filter; I’ve spent a lot of time looking at macro shots of CRTs and they were actually capable of sharp high-contrast edges, even a lot of crappy ones. Of course RGB is going to be razor sharp compared to composite video, and that’s probably what you meant, but I just wanted to clarify.

I’m not totally opposed to NTSC encoding, either, where it can actually benefit the image.

2 Likes
#523

Razor sharp comment was about your pvm/bvm presets, but yeah we’re good lmfao.

I’m over it lol. I just need to take a nap XD

1 Like
#524

All good man, we’ve all been there.

Anyway, here’s me playing around with NTSC filtering.

Super Metroid (JU) !-201205-211332
Super Metroid (JU) !-201205-2113321494×1120 730 KB

3 Likes
#525

@guest.r I need some help with the smart filtering options; what do you recommend for maintaining the bicubic look while softening/rounding the scanlines edges just a bit? I like how black lines remain sharp, but sometimes the scanlines don’t taper enough at the edge and just kind of get chopped off in a harsh way. Sorry if that’s vague, I think you know what I mean :sweat_smile:

4 Likes
#526

You can try as starting point:

  • Horizontal sharpness 3.0 (2.6 or less for AA, it’s on autoswitch)
  • Substractive sharpness 0.0 or a notch
  • Smart Edge interpolation : 2.0, 2.0 (starting point)

It should be (Edge Interpolation) quite safe to use with sharpness above 2.0 i think.

5 Likes
#527

NTSC preset I’m working on

Super Metroid (JU) !-201206-010604
Super Metroid (JU) !-201206-0106041494×1120 757 KB

mask 0 preset

Super Metroid (JU) !-201206-010619
Super Metroid (JU) !-201206-0106191494×1120 1.14 MB

Toggling between the two is fun. The background is better with NTSC, but the glowing head statues are decidedly worse and there’s less detail in Samus’ suit. It’s really hard to tell what the artists intended in this case.

3 Likes
#528

I think the statue heads look “ok”, they aren’t exactly bad but they aren’t horrible.

Ntsc preset is nice, kinda digging the mask 0 preset as well.

1 Like
#529

@guest.r

Coming back to your earlier post with the shot from the real CRT (see below), do you have an idea why the real CRT has a much less saturated image than the emulator output? Since I understand the CRT shot is from an RGB connection, it should be accurate saturation wise?

If I would like to mimic the saturation of the RGB Scart Philips CM8833 what would be the best way when starting from your default shader preset? Should I just be lowering the saturation parameter, or does that degrade the color fidelity in other areas?

3 Likes
#530

Camera is dicking with the saturation.

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#531

It comes down to more parameters:

  • different signaling
  • different chromatic and luminosity characteristics between CRT and LCD
  • physical layer of glass on CRT’s
  • one is screenshot, other photography
  • unknown calibration of CRT
  • …camera is tricking with the saturation :grin:
4 Likes