Gallica is the digital branch of the French National Library. It hosts the scans of a lot of rare old books, as well as of unique manuscripts. Many precious direct HEMA sources can be found there, for example:
It also gives access to a wealth of secondary sources.
Gallica has a specificity which can be a bit of a bother. If you use the zoom tool, you can see a lot of details, but when you try to save a particular page, your choice is between a (relatively) low-resolution export, or a high-resolution portion of the page. There just isn’t an apparent way to save the full high-resolution scan of a page. Obviously neither option really cut it if what you need is the actual full-resolution scan, for example to do a nice print or for further off-line study.
However, there is a way to get around that issue and access the full scan. Gallica implements the IIIF (International Image Interoperability Framework) interface. With a bit of URL trickery, this can solve the problem.
Let’s say you want to get that nice Lovino plate. If you look in the address bar of your browser, you will see this URL:
Now let us modify this URL like so. First remove the .item part to keep only the folio (on some documents or viewing modes, you might have to remove more, or different words; what you really need is to trim it down to the page ‘name’):
And then add a few parts:
The iiif means we want to access Gallica’s IIIF service, the first full means to get the full page, the second full means to get the full resolution, the 0 means no rotation, and finally native.jpg asks for the original quality in JPEG format.
This should give you access to the full-resolution color scan in all its glory! As you can see below, it is significantly better than the default Gallica export, which more or less corresponds to that IIIF request instead (even worse because they seem to do some color processing on top of it).
Gallica is not the only digital library with IIIF access, here are some more examples. Presumably you could apply the same sort of trick to get full-resolution scans there too, if their public interface has the same limitations as Gallica.