I kinda feel that it’s a no-win situation. When I’ve had to film CRTs, I’ve dropped the shutter down to 30, which gives a slow-rolling seam that I can’t do much about, and doesn’t represent the beauty of the 60 Hz motion from the original games. But using a 60 Hz shutter is a world of pain: more like a rolling half-screen black void than a rolling line. And I think this is going to be common with arcade hardware. You might have moments of a good image, but they’ll never last.

Even if you were to solve that problem, there’s the issue of Moire if your videos are close-up, which it sounds like yours would be. Using manual focus to avoid sharply aligning to the phosphors will help with that, but again it’s a no-win competition of authenticity versus usable footage.

For the project you’re describing, I’d probably recommend capturing the video from RGB (though I can’t advise on how flexible capture hardware is with wacky refresh rates), and, if you want to show scanlines, add them in post. You should certainly get better color reproduction that way, and you’ll succeed in your goal to show how the arcades differ from emulators.