What’s your favorite shader and why? 2019 Opinion Edition
My favorite is CRT-Hyllian.slangp
Why? Because it aims only for picture quality, so it avoids things that degrade the image just for accuracy. It, however, uses far less power to run, so it is possible to run this shader on lower end systems than CRT-Geom.
I’d ‘vote’ for ScaleFX. 
Being a longtime fan of scaling/smoothing shaders i just couldn’t go past by. It’s also a very cool platform for some aditional tweaks.
I’ll go for a simple one: sharp-bilinear-simple
It’s just enough interpolation to eliminate uneven pixel scaling artifacts like shimmering when scrolling. This is especially noticed on lower resolution screens (like 720p and lower).
Basically if you are not using anything and like that sharp pixel look, you should probably be using this.
crt-guest-dr-venom is the only CRT shader I need. Lots of options, but the defaults are excellent. Nice light scanlines and mask effects with just the right amount of glow. And the afterglow effect looks really neat; I noticed it a lot in Mario 3 in the first castle and Mario World during the Bowser fight.
I personally use a custom preset based on crt-royale, which is the best crt shader by far, in my opinion. I’m using tvout-tweaks and image-adjustment as first and second pass, and after that I apply all of the crt-royale passes. Final result is awesome.
I like and used some CRT shader variants, the current one I’m using is crt-guest-dr-venom, I tweak it a little depending on the system. I believe most artists and programmers created games with the TVs and monitors of the era in mind, so it’s nice to replicate that as accurate as possible. Sometimes I like seeing the other shaders with image enhancements too, they look cool and it’s always nice to have options.
Is it possible to have on over the other? For me at least it totally depends on the generation / console.
For Game boy I’m using motionblur/response-time and I’m very happy with it. For arcade shmups I’m still trying to find my favorite but for now crt-frutbunn works nice.
Yours! 
The biggest reason is the color management (adobeRGB, REC2020, etc). Why more people don’t raise a stink about it, I don’t know. Without this or some other complicated solution, most people with wider than SRGB gamut have to contend with ultra saturated colors. IMO it should be a setting within retroarch.
CRT-aperture is currently the best shader IMO in terms of ease of use and looking awesome with everything you throw at it. It’s got the options for scanline beam width variation, glow, and adjustable sharpness. The mask type takes into account the LCD subpixel structure so that the “active” subpixels are evenly spaced, like the phosphors on a CRT (many mask types result in uneven spacing of the “active” subpixels). The only thing it really lacks is some form of color management, but you can easily add another shader for that.
Here are the changes I like to make the default settings:
sharpness_edges and sharpness_image set to 1.00
scanline_shape set to 1.00
mask_strength set to 0.50
brightness set to 1.00
gamma input set to 2.4
gamma output set to 2.2
Increase LCD backlight as desired (100% in my case).
Ideally, mask strength would be 100% in order to get the RGB phosphors to display “accurate” RGB values, but anything higher than 50% results in weird-looking inversion artifacts with TN panels, and the vast majority of TVs today aren’t bright enough to max out the mask strength while maintaining an adequately bright image (only the Samsung QLED TVs and some brands made specifically for outdoor use are bright enough).
Past favorites include:
CRT-Easymode (hard to get it bright enough for my taste after increasing mask/scanline strength while maintaining a good looking gamma)
CRT-Geom (sharpness isn’t as adjustable as I’d like - ideal for me is between the lowest and next lowest setting)
CRT-Hyllian (I don’t really like what it does to gamma)
Also, I should probably add that the only reason Royale-Kurozumi isn’t on here is because my current dinosaur of a computer isn’t good enough to run it 
Well there’s the LUT-Shader and the Multi-LUT in the reshade folder. Do you need some LUT Files for these shaders? I guess i could make some that could help your gamut problems…
I love easymode. Looks great to me and runs well on low end GPUs. For potatoes i use Zfast.
For handheld stuff i use zfast-lcd. Haven’t really tried to many others. I like the simpletex ones but they look too fake to use all the time. For DS i use zfast_lcd_nds_hybrid which is fantastic.
The Game Boy classic screen shader.
A single screenshot of it was enough for me to start using RetroArch.
It’s “gb-shader”.
It’s located in the handhelds folder.
If you browse the actual folder in “shaders\shaders_cg\handheld\shaders\gameboy\resources” there are also some png files that change the palettte colors. You might want to change those manually if you like something other than the defaults. I chose this palette, it’s less green-ish than the default:
One of my favorites as well, amazing how we can play handheld games with this fidelity in any resolution.
In this picture, we can clearly see that 4k can’t handle the green tint, this glory is only available at 8K and above.
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