Help understanding resolution settings

Hello all,

I’ve been playing with UE for a week and I love it !

I’m though a bit confused about how to manage project resolution and work with it.
Please note that I’m not into game development and intend to use UE for Filmmaking / Motion Graphics / Live Visuals, and I have a background as a 3D Motion Designer.

So, I actually don’t really understand where and how a project’s pixel resolution is managed… I know that you can seemingly setup the Level Editor resolution in Editor Preferences > Play > New Viewport Resolution but some things bug me out :

> I tried to set it to a very low setting like 192*108 and I don’t see any effect neither in preview or game mode, everything is still finely displayed and detailed !

> Working on a scene, behaving fluidly, when going fullscreen with F11, it starts to lag so it probably means UE tries to render it at my screen’s 2560*1440

> How can I display my scene, whether in preview or game mode, in a 1x1 “real pixel size” view ?

To put it in another words, how can I setup my scene at for example 1920x1080 pixels, and keeping that resolution when going fullscreen ?
I know that when rendering out a movie I can specify desired resolution, but I would like to understand what is my displayed resolution, be able to see it at real pixel size, and in case of live visuals, working at a specified resolution that I know has a good FPS on the machine that will play it.

Thank you in advance for your help !

the viewport that is looking at the level is the effective pixel size
you can drop the screen percentage render amount by clicking the down arrow in the top left of a viewport and changing the screen percentage value
rendering resolution is handled by the camera and the movie render settings