This is the background for my skyscraper shot. The terraformed Mars that I've used before. It was rendered in Vue Infinite.
Then the terrain and skyscrapers were added. And some clouds. I like that the stars show through. The above background is being used as a backdrop here. It fills the camera frame (720 x 1280). If I rendered the entire scene together, the light would bounce up from the terrain and light up the entire planet. That could work as well, bringing a more surreal look to a scene.
The buildings were left unpainted for now.