There's a camera mode in Terraria (F1) that takes snapshots and allows you to capture a user-defined frame beyond what's viewable on the screen. Whenever I take screenshots this way, the moon doesn't show up (or the weather... rain does, but gray haziness doesn't). How do I use camera mode to capture the weather as well?
You cannot capture the sun, moon or certain weather effects with the in-game camera mode. In the camera settings, there is a toggle for entities, but this only includes "living" things like the player, NPCs, monsters, and pets. You can also disable the entire background. The only way I can think of where you could make this partially work is if you took an image with the in-game camera, then took one with Steam (F12), and then edited the moon/sun into the image afterward. For weather this wouldn't work though. You could theoretically take multiple Steam screenshots and edit them together for that.