In order to scan large foldouts in fragile books we’re using photogrammetry to produce an orthomosaic at ~600dpi using a Hasselblad H5D60 and a camera dolly. This overcomes stitching errors using traditional image stitching methods which only work well with perfectly flat items.
The book hiding underneath all of this: http://cat.lib.unimelb.edu.au/record=b2984157
The final output was an orthophoto created from a DEM with an effective resolution of 508DPI. This will increase to 600DPI for final production.