I’ve just discovered this free, open-source software. It is web-based; designed to catalogue, manage and publish archival or museum collections.
there is a demo version at:
Technical stuff is on the wiki:
The most useful feature for curators of art and design images is the built-in vocabularies notably the Getty Art and Architecture Thesaurus and the Library of Congress subject headings.
Other observations: Search options seem a little limited. Images can be uploaded. Open Access can be integrated with Fedora.