Q: How big should the background image be?

A: The background image should be larger than the size of the 3D window. In general, the resolution ratio is set by default. For a 3D scene background image, it is recommended to have a size above 10001000 for standard resolution, above 14001400 for 2K resolution, and above 2000*2000 for 4K resolution. This ensures a clearer 3D background image effect and prevents blurring due to stretching.