Since its relatively recent introduction, Tropy has been hailed as a game-changer for historians, in part because it is (the only?) software created precisely with helping historians manage their archival images in mind. Tropy offers users the ability to easily organize photographs and PDFs gathered in the archives, add important metadata (including archival record location details), as well as annotate the images themselves with notes. Users can also tag their images for further organization. Multiple images of one document can be easily grouped together into a single document, and multiple documents can be grouped into collections.
For even more functionality, you can export information to JSON-LD and to Omeka.
Tropy is designed by the Roy Rosenzweig Center for History and New Media and is funded by The Andrew W. Mellon Foundation.
Tropy is available for Windows, Mac, and Linux 64-bit. It is free and open source.
Tropy has a robust user guide that makes it easy to get started, as well as active forums.
There are still occasional bugs to work out and new features that users would like to see (see the forum for posts about these), but it's worth noting that the Tropy team seems to actively be listening to feedback and working on updates to increase functionality all the time.