About Scanning: When scanning your images, you are usually prompted to choose what resolution you would
like your images scanned at. The intended use or display of your images will help you make this choice.
Printing: Images intended for high-quality printing should be scanned in at no less than 150dpi, preferably
300dpi. Remember, dpi is “dots per inch”, and the more dots per inch, the sharper and crisper your images
will look on the printed page. Many publishers have minimum resolution requirements for digital image
submissions – make sure you know what’s required before you start digitizing.
Computer display: Images intended primarily for display on a computer monitor (such as email
attachments or images on a Web page) really only need a 72ppi to 96ppi resolution, as that is what computer
monitors are capable of displaying. A higher resolution will not make your image appear any better on the
screen. In fact, if you don’t expect folks to print out your images, these images should be “optimized”,
which means making them as small and compressed a file as possible (while still retaining the appropriate
visual clarity), so that they load quickly, and do not take up too much space on the hard drive.
TIP – if you need to make high resolution, large files available via the Web or computer, create “thumbnail”
versions of your images that then link to the larger images. This prevents your viewer from enduring slow
loading times for images they are not interested in seeing.
TIP – Optimizing images for computer/Web display involves compression, which throws out some pixel
data. You cannot then enlarge the images without encountering pixelation
Re: Digital Imaging Basics by Melanie Cofield
Information Technology Lab
School of Information
The University of Texas at Austin