Understanding scanning resolution for corporate, archival and specialist documents.
What is scanning resolution?
Scanning resolution describes the number of image samples captured per unit of the original, commonly expressed as pixels per inch or PPI.
Is 300 PPI enough for documents?
300 PPI is widely used for many document applications, but the appropriate resolution depends on the source, detail and purpose.
When is higher resolution useful?
Higher resolution can be useful for fine handwriting, small type, detailed drawings, maps, photographs or material where future enlargement matters.
What does National Archives guidance say?
NARA's scanned textual-record guidance specifies different minimums according to the source: bitonal 300–600 ppi, greyscale 300–400 ppi and colour 300–400 ppi for the contexts covered by its guidance.
Does higher resolution always mean better?
Not automatically. Resolution should be high enough to capture the required information without creating unnecessary file size and processing burden.
What about archival masters?
The project specification should be agreed based on source characteristics, preservation objectives and intended use rather than selecting one resolution for every record type.
Frequently Asked Questions
Should corporate documents be scanned at 300 PPI?
Often 300 PPI is suitable for ordinary text, but the correct specification depends on the document.
When should I use 600 PPI?
Higher resolution can be appropriate where fine detail, small text, handwriting or archival requirements justify it.
Does 600 PPI make OCR better?
It can help where the original contains small or difficult text, but OCR accuracy also depends on contrast, paper quality, typeface and layout.
Further Reading
Oxford Duplication Centre — Practical Expertise
Professional document digitisation depends on matching the capture method to the original. Modern loose documents may suit production scanning, while fragile, bound, oversized or unusual records need specialist handling and equipment. The aim is to create reliable digital records while protecting the original material.
Need DAT tapes digitised?
Oxford Duplication Centre provides professional DAT digitisation for individual tapes and archive collections, with preservation and access outputs tailored to your requirements.
WAV Audio Digitisation Request a Quote