Max Resolution limited to 4096x3072 (12,58MP)

I forgot System Details:
Fairphone 5
e/OS/ 3.1.1, Android 15

Are you referring specifically to the original OpenCamera, or are you using a fork of the app that is used in e/OS?

Because OpenCamera generally does not support large resolutions on all smartphones.

But I think e/OS did something to make higher resolutions available on their fork, at least on Fairphone, from what I remember or recall.

I am using the original app from f-droid
With the Camera app in e/OS/ (if thats the fork you are talking of) a setting of 8192x6144 (50,33MP) is possible

Well, maybe Mark will take a look at this -
https://gitlab.e.foundation/e/os/camera/-/merge_requests/78/diffs?commit_id=0126b2da12c485d6feeea3064d62ba2bd926bfed

and maybe it will bring some kind of solution.

https://gitlab.e.foundation/e/os/camera/-/merge_requests/91/diffs

"The FP5 has a 50MP Camera (8192x6144 (50,33MP) and this is usable with other camera apps"

Which non-stock camera apps have 50MP resolution on the Fairphone 5?

Thanks for the links to the e/OS fork, that's interesting - ideally I'd stick with the standard Android API rather than using device specific routes (the device specific strings for the keys), there's the risk that even if it works now, it could change in future. Ideally FairPhone would expose this either directly, or via https://developer.android.com/reference/android/hardware/camera2/CameraMetadata.html#REQUEST_AVAILABLE_CAPABILITIES_ULTRA_HIGH_RESOLUTION_SENSOR (which Open Camera admittedly doesn't yet support, but it would still need devices to support it too).