The Metropolitan Museum of Art has nearly 400,000 images online, almost all now in ‘just about’ print-res, and…
“that the Museum believes to be in the public domain and free of other known restrictions; these images are now available for scholarly use in any media.”
Above: “A Fury Riding on a Monster”, by Cornelis Saftleven, mid 17th century.
A sample download gave me a 72dpi picture at 3000px on the longest side, which (with a bit of Photoshop work) would just about hold up at A4 size and be able to fill a full page of a print magazine.
It seems the Met is actually being a little whiffly with its rights claim. In the USA it’s apparently well established in law that… “faithful reproductions of works in the public domain do not attract new copyrights”. Therefore, the Met seems on shaky ground regarding its statement that the images are for scholarly use only.