[Other Question] EBS Battlebacks and how to format custom ones(?)

[ArchyTheArc]

Very unsure how to create a custom background that fits the ratio of the screen, feel the background is blown up by 2 or 4 times due to the zoom, only seen one being spectrum change the backgrounds but they also changed their screensize,

just wanna know how it works and stuff so i can make custom ones ^^ (like whats in frame mostly/with the camera movement off, and whats mostly out of frame/seen breifly in movements)