Dolphin does not display extended file properties for new files. Only standard properties are visible: file type, size, modification time, tags, stars and comments. No EXIF and so on. These metadata are visible after file indexation (on KDE Neon by default after reboot or manually). The problem does not occur on external drives. As far as I know, in that case indexation is turned off.
1. You have latest KDE Neon User Edition
2. You will wait a moment to finish indexing files after the system starts
STEPS TO REPRODUCE
1. Download file with additional metadata (e.g. this photo with EXIF: https://github.com/ianare/exif-samples/blob/master/jpg/Canon_40D.jpg) and save it on main disk (not external)
2. Open Dolphin and find downloaded file
3. Right click -> Properties
Only standard properties are visible: file type, size, modification time, tags, stars and comments.
Standard properties + some other metadata like camera model and so on
Linux/KDE Plasma: KDE Neon User Edition 5.16.3 (Linux 4.18.0-25-generic)
(available in About System)
KDE Plasma Version: 5.16.3
KDE Frameworks Version: 5.60.0
Qt Version: 5.12.3
Missing metadata are visible after file indexation (on KDE Neon by default after reboot or turn it manually). From what I see, file indexation is not continuous.
Tested on two different computers (including fresh installation from neon-user-20190711-1118.iso).
The indexer is what's responsible for showing this information. Until the files are indexed, they won't show it. We can try our best to make it faster, or maybe show a notification on first boot that indexing is happening and that some performance and features might be impacted until it's done (they do this on macOS). But in the end you're just gonna have to wait until indexing is done.
To track a notification that tells you this information, I've filed Bug 409881.
I think I have disabled Baloo (I disabled file search in KDE settings a long time ago), but I can still view the metadata of Canon_40D.jpg. I somehow cannot reproduce this bug.
Thanks for quick answers.
As I wrote before, the problem does not occur on external drives. Additional metadata is visible instantly. As far as I know, in that case indexation is turned off. How does it work in this case?