Losing quality in pictures

I’ve been trying to upload photos to Nextcloud using an iPhone, but the app doesn’t seem to work properly. It often crashes, and when it does, the user session closes, forcing me to delete the uploaded pictures and re-upload the entire folder to avoid duplicates.

Since I have a large number of photos, I tried splitting them into folders of 500 pictures each, but that didn’t solve the issue either.

My biggest concern is that the photos are not being uploaded in their original size, which makes them look different. On my iPhone, I do not have photo optimization enabled, and in Nextcloud I have the format conversion option disabled.

Has anyone experienced the same problem or knows how to fix this?

For the quality, do you have the “Most Compatible” option enabled in the advances settings?

The auto-upload has been working reliably in the past for me, you just have to open the Nextcloud app from time to time (I have not enabled the GPS-trigger “Enable Background Location”), so it triggers all uploads properly.

However, this month, the sync got completely blocked, I had to upload everything since end of August up to now, and restart the whole sync process. I don’t know and unfortunately didn’t have the time to check in more detail, what triggered this problem (specific update of server/client, ….).