Update Immich writeup

[kanecko]

I went in too much detail, accompanying each user-action with its own screenshot. Identify and remove unnecessary screenshots.
Crop images containing too much whitespace. Possibly also resize them, if necessary.

Add ".. warning::" or ".. note::" notations.
Candidates:

Real world usage data for Immich v2.2.3: for ~70k photos/videos, up to 4GB (8GB peak) of RAM is normally being used. CPU usage is mostly negligible, but it will shoot up when new files are ingested.

This can be controlled via the administration settings. See: :ref:immich_other_settings.

WARNING: Write access!

Mounting an external library of photos/videos via the Web-UI will give Immich write-access by default. This also means you will be able to delete files via Immich.

If you want to restrict Immich to read-only-access, you will need to do the following instead:

    download the [Immich Rock-on configuration file](https://github.com/rockstor/rockon-registry/blob/master/immich.json),
    save it under /opt/rockstor/rockons-metastore/,
    edit the file: toward the end of the file, right after [ "-e", "DB_HOSTNAME=immich-database" ], insert the following line: , [ "-v", "/mnt2/MyPrivatePhotoCollection:/mnt2/MyPrivatePhotoCollection:ro" ], where /mnt2/MyPrivatePhotoCollection is the path to the share where you keep your existing photos/videos,
    save file,
    in case your Immich instance is already running: go into the "ROCK-ONS" menu, find the Immich Rock-on, set it to OFF, afterwards click on the Uninstall button,
    now re-install the rock-on.

Note that there is currently no good central sharing solution present in Immich! If you wanted to have a central repository of photos/videos that is shared between different users, immich-app/immich#12614 until it's implemented.

Until then, here are some alternatives:

Create a single user account that you share with other people: all people and devices will have access to the same library with all people/facial recognition data (and other metadata), and they will all be able to upload their own files to the library. Duplicates are detected on the whole library.
[Use partner sharing](https://docs.immich.app/features/partner-sharing/): other users will be able to view and download files (and their metadata) from your library, but won't also share the people/facial recognition data. You won't see other users' libraries automatically - they have to explicitly share back. Other users can't upload their files to your library. Duplicates are detected only on your library. Smart search and map features won't be shared.
Create user accounts for each family member and one additional account with the external library, then using the partner sharing feature, share the external library with other users.
Set-up the same external libraries for each user: causes unnecessary file metadata duplication.

[phillxnet]

@kanecko Thanks for opening this issue. I'm also wondering if the custom Rock-on guide section re read-only is a step too-far myself. Nice but may be over-the-top. Maybe just the warning you given re write-access and a terse note re potential :ro custom modification. Also consider bullet-points for long lists of steps.