Artstor offers free access to all public collections from library.artstor.org
The Public Collections is a freely accessible library of images and other media where you can search and browse collections with tools to view, share, download, cite, and print media. [This a subset of the Artstor database that UCC Library subscribes to, and is available to anyone whether they have access to the complete, subscribed database through their Library's subscription or not].
See information on the public collections available on Artstor here.