Catalogs
Each time a tape is mounted, Canister will create a Catalog for it. Canister Catalogs are special folders containing tiny stubs for each file on your tape, and are mounted as a read-only disk each time Canister opens.
As Canister creates a Catalog when mounting, and updates it after each Archive, old Catalogs are archived as well and moved into a hidden folder named LTO Tape (serial).history
Enable Finder to show hidden files to see previous generations of your Catalogs, with the Finder shortcut Shift-Command-.
To clean up the Catalog, or remove for instance test entries, you can open the original location where the stubs are saved by Alt/Option-Clicking the Catalog icon in Canister. This will open Finder in ~/Library/Application Support/Canister/Catalogs.
Currently, it's not yet possible to use Catalogs to tell Canister which files to retrieve. This is on the roadmap, together with importing and exporting of Catalogs.
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