Scan handling

Documents are digitized as preservation copies before indexing. The Digitization Unit records scan quality, OCR confidence, source condition, copy status and manual review requirements where available.

Damaged or low-contrast source copies are retained when their administrative value is higher than the quality loss introduced by digitization.

OCR confidence

OCR confidence is an internal quality estimate produced during text extraction. Values below the current threshold are routed to manual verification according to Procedure 4.2.

Low OCR confidence does not automatically remove a file from public access.

Equipment notes

Flatbed units S-02 and S-04 are referenced in scanner logs. Equipment Services maintains calibration entries, glass replacement invoices and service records.