Maps and Charts
NARA defines these records as graphic representations, drawn to scale, of selected features of the surface and atmosphere of the earth and of other planets and planetary satellites. Examples include hydrographic/nautical charts, weather charts, aeronautical charts, photomaps, orthophotomaps, atlases, cartograms, globes, and relief models.
Maps and charts tend to contain fine detail and are also usually oversized. The ability to reproduce very fine detail and/or accurate color from a very large original can be a challenge.
Scanning oversized originals can produce very large file sizes. It is important to evaluate the need for legibility of small significant characters in comparison to the overall file size when determining the appropriate scanning resolution for oversized originals.
Because oversized materials are generally digitized on a copy stand setup, the possibility of images being evenly sharp (they may be less sharp around the edges due to the limitations of the lens of the camera) may be a factor in the quality of the scan.