Of course! Here’s how I’ve got the B&W Borrowed Time to look like that:
#reference "shaders_slang/bezel/koko-aio/Presets-4.1/tv-NTSC-1-classic_take.slangp"
NTSC_MIX = "3.000000"
NTSC_FILTER_SCF = "3.75"
DO_SPOT = "0.000000"
The Subcarrier Frequency Mul (NTSC_FILTER_SCF) parameter is the key. As you increase or decrease it the colors will change wildly, until you find a sweet spot where they get “stabilized”.
Here we have The Bard’s Tale (Apple II), in B&W:
Now, the same game with the “tv-NTSC-1-classic_take.slangp” preset and the parameters specified above:
If I change the “Subcarrier Frequency Mul” from 3.75 to 3.74, I get this mess instead:
There are other spots where the colors get stable, though, although the palette gets quite different. I’d guess that for some other games/systems you’d have to fiddle with this value until things get right.
Here’s what I get with a value of 5.25:
And here’s the rather cursed/cool 6.00:
For comparison’s sake, here’s the raw image of the game in color mode: