Automatic Document Feeders
Scanners and photocopiers with Automatic Document Feeders (or ADF) permit faster document imaging than the “one page at a time” approach of a flatbed scanner or glass platen would. However, the reputation for documents being damaged in ADF equipment exists. So much that NARA and other cultural institutions are typically prohibit Archival documents from being scanned or copied in ADFs. This photo shows damage that can result when a document is jammed inside an ADF.
{picture one }This photo shows damage that can result when a document is jammed inside an ADF. {picture two} The amount of time it takes to repair such damage far exceeds the time of taking a more careful scanning approach. {picture three} This is an example of repairs to a document damaged in an ADF.
Most document feeders use a high curvature paper path to turn over documents (usually to preserve stacking order or to flip for imaging the back side), and this places tension on already torn, brittle or otherwise fragile documents, especially in high-speed / high-volume operations. Even with originals in perfect condition there always exists the potential for machine malfunctions or human error resulting in damage. Failing to detect staples or tape holding pages together prior to feeding documents will likely result in damage in an ADF. Another general objection to using ADFs (most relevant for intrinsically valuable originals) is that rubber and urethane rollers come into contact with documents, introducing residual chemical compounds that might affect paper condition over time.
Some ADFs are now engineered with the aim of scanning less than perfect paper (such as torn or bent pages). These ADFs minimize risk to documents by reducing the degree of curvature and in some cases employing a straight paper path. If you must use an ADF and can risk some damage, it’s best to use a straight paper path document feeder.