So I just finished up my poster and I wanted to export it, so I turned on Progressive Refinement, and noticed one thing. Enabling "Subpixel Jitter AA" in the Render Settings somehow messes up the lighting both in the viewport and in the render. I have no idea what's the deal and I do need to use the AA, so turning it off is not an option.

Here's what the viewport looks like with Subpixel Jitter AA disabled :
https://i.imgur.com/4XGove8.png

And here's what it looks like with Subpixel Jitter AA enabled :
https://i.imgur.com/2eYEYBy.png