According to the official documentation,
With the camera placed upside-down, the image must be rotated 180° to be displayed correctly. The way to correct for this is to apply both a vertical and a horizontal flip by passing in the -vf and -hf flags:
raspistill -vf -hf -o cam2.jpg
An astute reader will also notice that
-rot 180 yields the same result.
So in the use case of a raspberry pi zero w with official camera (noir or daylight), which is more efficient?
power-management tag because I'm wondering if this could impact lower-power usage deployments.