
	ACS Home Page
	Academic (Technology) Roundtable
	Academic Media Studio
	Blackboard
	Classroom Recording
	Classroom Technology
	Communications Tools
	Faculty Support
	Media Resources
	Research Computing & UNIX

Scanning basics (glossary)

Save an archival version
Unless you know that you will never need a digital image beyond your immediate purpose, it is a good practice to save an archival version of the scan in TIFF format. Create a working version of the file for the web or print.

Determine the image size
The following chart provides guidelines for image size and resolution. Screen sizes reflect browser frames. While you can always scale down an image's size, scaling it up may lead to a loss of quality.

Media type	Capture method	Capture resolution	Archival format	Screen format size/quality	Mime type, Extension
b/w text document	flatbed scanner or digital camera	1-bit, 600 dpi	TIFF	PDF	application/pdf .pdf
photos, illustrations, maps, manuscripts, etc.	flatbed scanner or digital camera	8-bit grayscale or 24-bit color 300 dpi	TIFF	JPEG 150x150 pixels 780x470 1000x610 1250x870 Quality: High (60)	image/jpeg .jpg
35mm b/w & color slide or negative	slide scanner	24-bit color 3000 pixels (longest side)	TIFF	JPEG 150x150 pixels 780x470 1000x610 1250x870 Quality: High (60)	image/tiff .tif

Set the scan resolution for screen or print

For web or screen, a resolution of 75-100 pixels per inch will produce a final screen image approximately the size of the original.
For print, image resolution is a function of the printer's capability. 150-200 pixels per inch is more than adequate for a 600 dpi laser or inkjet printer.
Scan at 300 ppi if you do not know the final size of the printed image, or to create an archival version of the scan.
When working with a publisher or commercial printer, ask their production staff for guidance.

Set bit depth or 'image type'

24-bit, 'millions of colors' or 'true color' for all color photos or artwork
256 shades of gray for black and white photos