This feature Introduced in LUNA v7.4.3, Item Level Restrictions are set in the LUNA Library allows for restricting items . This feature allows collection owners and Super Admins to restrict media items or media items & records in a collection and , then granting grant access to those restricted items to a smaller set of users or credentials. Restrictions are applied to items both in the Viewer and the Library (not one or the other). Super Admins and the owner of a collection have full access to all items, regardless of the restriction. A collection owner can also Only a Super Admin can pass collection ownership to another user and in doing so the previous collection owner will no longer have the collection owner status.
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You can also click on "Modify" to get to the thumbnail view for media items that were selected for that Restriction.
Search for Restricted items in Library:
As the collection owner or Super Admin, you can search a collection in the Library to see what items are restricted or not restricted. The choices are: Not Restricted, Media Items Restricted and Media and Records Restricted.
After performing an Other Criteria advanced search for either media restricted or media & record restricted, an additional drop down list of users and credentials that are potentially excluded from the restrictions will be displayed on the left hand side. The list should be located on the left hand side of the results, right below batches.
When you click on a user name or credential from that list, the result will show all items that the user has access to within the restricted items.