Composite to RGB comparison chart
Bottom taken from emulation, top from my capture card. Constrast and saturation set to default levels. Brightness set to normal level (little bit above default). But really, it doesn’t matter. You can clearly weird Luma stepping in the color transitions. If you turn the contrast up, or brightness down, or even turn the saturation down so the screen is black and white – it has no effect on the relationship of each color to its neighbor. The odd stepping it already there.
I suspect it’s either an error in the original table (and this is from an SGX, so it has a second revision VCE) or it’s because 5bits per channel isn’t enough for the color conversion to carry over correctly and you get stepping errors. Either or, it’s pretty significant. Like I stated before, SO2 simply looks great with this color mapping. It makes me want to go back through the PCE library of games where I thought the color choices were poor and re-check them.
I hate to sound like a purist, but if I were to have to choose between which color set is appropriate and which is incorrect – I’m definitely leaning towards the VCE table converted set. That means GFX tools, general graphics, etc with that in mind.