When you use OpenGL as the rendering mode for Roblox your capture service image results are terrible quality. The easiest way to check this is to use Roblox’s built in capture feature and then view the results.
I did this in studio and have been unable to confirm if this also occurs on the client (but I assume it does if the client uses OpenGL)
OpenGL for whatever reason entirely breaks screenshotting as a whole. Though ive mostly noticed this to happen at much higher resolutions like at 8k and higher.
