I love medieval art, and am interested in scanning images of angel paintings and sculptures from recent books on religious art and printing them onto greeting cards for resale. All of these books were printed recently, and are available in bookstores, but the images are not currently sold separately. The medieval artwork itself is all from the 12th and 13th centuries. Do I need to get the permission of the publishers of the books before proceeding?
There is no doubt that the medieval artworks are not protected by copyright. Any work in the United Stated published before 1923 has fallen into the public domain, so that is certainly the case for works made in the 12th and 13th centuries! The artists who painted and sculpted those angels have passed away long ago.
But that does not mean that you can simply copy photographs of those works. A separate copyright exists on the photographs of the angel paintings and sculptures. The authors and/or publishers of the books that you are examining paid photographers to travel to museums around the world and take photographs for reproduction. The photographs are covered by their own copyrights, pursuant to 17 U.S. Code § 102(5). Most likely, the books' publishers now own those copyrights, since they probably purchased them from the photographers.
Some courts have held that a photograph that is a "slavish copy" of a work in the public domain is not protectable. See, for example, Bridgeman Art Library Ltd. v. Corel Corp., 25 F.Supp.2d 421 (S.D.N.Y. 1999). Under this theory, a photograph of a 12th century angel that merely shows the angel with no originality of its own cannot be separately protected by the modern-day photographer.
However, this rule is narrow. A photographer who can claim that he or she exerted any amount of originality or creativity in the photograph will likely be able to establish copyright protection. This is especially true for photos of three-dimensional works such as sculpture, or photos of artwork where the photographer exhibits some originality in the lighting or composition (for example, a photo of the Mona Lisa that is lit it in such a way that only Mona Lisa's face is visible, not the background).
Therefore, it is risky to start scanning and copying photographs from a book without the publisher's permission. You would not want the publisher to discover your greeting card business online and initiate expensive litigation against you. A safer course of action would be to either (i) ask the publisher for permission beforehand; (ii) use open source photographs of medieval works of art, which many university art libraries offer; or (iii) visit museums and take photos yourself, in which you would have the exclusive photo copyright over the public domain works.