The New York Public library recently released 180,000 of its digital scans into the public domain. The works include manuscripts, sheet music, stereoscopic photographs as well as maps that are free to use for any purpose.
These images should be especially useful to those photographers who like to combine and overlay images for graphic art or illustration purposes. A rather interesting tool for browsing the images can be found here
From the New York Public Library Blog
Today we are proud to announce that out-of-copyright materials in NYPL Digital Collections
are now available as high-resolution downloads. No permission required, no hoops to jump through: just go forth and reuse!
The release of more than 180,000 digitized items represents both a simplification and an enhancement of digital access to a trove of unique and rare materials: a removal of administration fees and processes from public domain content, and also improvements to interfaces — popular and technical — to the digital assets themselves. Online users of the NYPL Digital Collections
website will find more prominent download links and filters highlighting restriction-free content; while more technically inclined users will also benefit from updates to the Digital Collections API
enabling bulk use and analysis, as well as data exports and utilities posted to NYPL's GitHub account
. These changes are intended to facilitate sharing, research and reuse by scholars, artists, educators, technologists, publishers, and Internet users of all kinds. All subsequently digitized public domain collections will be made available in the same way, joining a growing repository of open materials.