How to fix stretched pixels on screen edge (post process)

Hi everyone !

I need some help on post process materials please. I’m pretty new to this, I went throught Ben Cloward videos to try to achieve the effect I want. (from 49 to 52 Basic Post-Processing Effects - Shader Graph Basics - Episode 49 - YouTube)

What I want : I have a straight plane that I want to make it look “rounded” on the edge of the screen. The reason is that I want the character to move inside a big cylinder, just like some space station in movies where the living space is in a rotative ring to simulate gravity. The fact is that modifying gravity seems a lot more complicated than faking the visual effect. Doing it through post process would be ideal because my whole level could remain straight, so easier to deal with.

For now, I came up with this :

I’m pretty happy with the result for now but I have those stretched pixels on the right edge of the screen. It’s logic because I offset those pixel to move from that edge to make the plane look round a bit, I suppose Unreal fill the “empty” space with the same pixels.

My question is : is there any way to fix this ? By taking offscreen pixel in account for example ?

Thank you in advance !