Wow, this came just in time. Played around a little with the Panini Projection and it does help with the distortion. The blurriness is there too so that leads me to think I’ll need to review the UT Github’s repository and study what they did. I haven’t really played around with UE materials too much so this looks like a good time to do so.
Ideally I’d like to render one set of geometry into the backbuffer with one projection matrix, and another set of geometry with a different projection matrix. But I gather from your statement above that’s probably not an option.