Is there any shader that can imitate rainbow effect from Megadrive?

RetroArch Additions Shaders
#1

Greetings people.

I’m looking up for a particular effect that comes along with composite connection for MegaDrive/Sega Genesis games that I haven’t managed to find any shader/preset that could replicate or at least get something close enough to this effect inside RetroArch. This is an example of what I say in Sonic 2 - Chemical Plant Zone - Real hardware where you can see this rainbow effect over pipes.

Do you know if there’s any shader/preset that can get something similar or the closest possible ?

I would appreciate any help you can ever bring.

#2

I think the easiest way to do it is with the NTSC filter built into genesis plus gx (accessible via the core options).

#3

Unfortunately this doesn’t bring up a close enough result as the one in the video, I appreciate the reference though. There’s a mix between green/red/blue over there but unfortunately there’s not much info related to this effect or if any developer focus on it.

#4

IIRC, the rainbow banding has less to do with composite and is more an oscillator/crystal synchronization issue between the video components. This timing issue isn’t present in the 32X video encoder, which doesn’t have the banding. As an aside, Sonic Jam on the Saturn doesn’t have the banding either.

I’ve tested these all on original hardware on a CRT TV. All through composite.

You might have more luck finding info on this if you use the search term “rainbow banding”, though I’m not sure if it’s something that can be replicated with a shader.

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