Game runs at 480x270 so doesn't scale well and game devs of course didn't figure out they need to first upscale image using integer scaling but then downscale it using linear for other resolutions than multiples of 270p like 1080p, 2160p, etc. Had to use ReShade to do it myself to fit what my downscaler expects which is 1728x972 to then be converted to 1728x243 pixels with chroma subsampling. Or 1728x972 using quad-interlacing shown in the last photo. Imho its best to use progressive low line mode to get this classic scanline look.

BTW. I guess PS5 version won't have such issues needing ReShade and such as console doing its own downscaling so it will be piece of cake to downscale from 720p to 240p or use overscan compensation feature to shrink image enough to more or less fit to 243p using 4:1 downscaling.

Of course downscalers with actual scalers like OSSC Pro should be able to downscale to 240p without needing external prescaling. I have not tested how well it works in practice though and the main reason is that 1.5 frames of lag on CRT is off putting to me and why I made my own dowscaler in the first place. Of course OSSC Pro (and RetroTink 5x/4K) can also do line dropping/decimating without lag and this being PC version and ReShade obviously works on it there are ways to prescale image in ReShade to 240p then integer scale it for OSSC Pro/RT/etc. and avoid lag that way.

BTW. I will be releasing FW this month. Most likely you'll need JTAG because so far there is no progress on implementing SD card support. Recently added 960x720 support for 4:3 CRTs and aspect ratio correction - all of my CRTs seems to have slightly different aspect ratio and while I could perhaps just figure out what aspect ratio is correct using e.g. OSSC Pro as reference and tweak my CRTs I guess that wouldn't solve issue for anyone with similar issue. In this case aspect ratio can be corrected using different pixel clocks so there is no scaling / quality loss.

Ninja Gaiden Ragebound on Ikegami TM20-17R using OSSC Zero