Enhance a scanned document and check every character

A flat page pressed onto the glass, squared to the edges and lit evenly, gives an upscaler far more to work with than a hand-held photo taken at an angle under a ceiling light. Aim for 300 dpi when the page only needs to be read on screen, and 600 dpi when someone may later zoom into footnotes, small print or a table. Remove staples, unfold creases, and avoid flash, because a glare hotspot can erase text that the paper itself still carries.

Once the capture is clean, decide whether enhancement is warranted at all. If the scan is already sharp and evenly lit, an extra pass may add little beyond file size. Enhancement is most useful when a slightly soft page must be enlarged for reading, or when an old scan was made at a low resolution that cannot be repeated because the paper has since degraded or been returned to an archive.

Text is the hardest thing for any pixel predictor to handle well, because letters are small, high-contrast and full of meaning. A stroke that gains weight, a digit that gains a little tail, or two characters that merge can turn a correct number into a wrong one while the page looks cleaner overall. The tool raises pixel count and may sharpen perceived edges, but it does not decide what a character should say; that judgment stays with you.

Optical character recognition is a completely separate job. Enhancement does not read the page, does not produce selectable or searchable text, and does not fix a misread. If you need editable or indexed text for a contract, a legal filing or an archive catalogue, going back to a re-typed or vector original always beats an upscaled bitmap, because a fresh original carries no invented characters at all.

Compare the enhanced result against the paper original, not merely against the earlier scan, and read every number, date, personal name, account reference and monetary amount one by one. Check faint stamps, signatures and seals too, since a predictor can add or merge marks that were never printed. Anything that will be relied on for money, identity or legal rights deserves a second pair of eyes on the physical document.

Keep the untouched scan as the copy of record and treat the enhanced version as a convenience rendering. Before uploading, remember that a scanned page is sensitive personal or business data: remove pages you do not need, and think about retention obligations before sending a statement, contract or identity document to any online service. Download an acceptable result promptly and delete what you no longer need.