Oppo
Turn Grid Lines On or Off in Camera auf Oppo
Grid lines overlay a rule-of-thirds pattern on the camera preview to help you align horizons and edges. Oppo phones running ColorOS usually ship with this overlay switched off, so nothing appears in the viewfinder until you enable it manually.
The setting lives inside the composition menu and is stored separately for photo mode and video mode. That is why the grid can be visible while taking pictures but missing when you switch to recording, or the other way around.
To turn it on or off: Tap on Camera ➔ Tap on Settings ➔ Tap on Composition ➔ Choose Photo or Video ➔ Enable or disable Grid.
The lines only appear on screen while you frame the shot. They are never written into the saved photo or video file.
Skip this setting if you already rely on a level indicator or gyroscope horizon guide, since both address the same alignment problem without adding extra lines to the preview.