Scan image

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Scan an image

Sources:

Handwritten text, such as a letter or an ancestor’s birth certificate
An illustrated page, with text
Just the image or graph on a page: select the image, scan it, then crop and edit it with the imaging software
A photograph or picture postcard
A slide -- also see below

Decide before you scan

Do you want to print the image? In that case, scan it at the highest possible resolution and save it in a non-lossy, non-compressed format: TIFF or BMP.
Do you want to use the image on a web page? In that case, scan it at the lowest possible resolution and, after editing, save it as a .jpg/jpeg file, compressed.

What size do you want? Full page, 4 x 6" photo, 2 x 3" on a web page?

Let the scanner do the work. Adjust all settings to the intended area, size, resolution, color BEFORE you scan.

Explanation: Adjustments of size, resolution, color should be left as much as possible to the scanning software. Later editing of these properties may make the image blurry, grainy, whatever. Resizing an image for the screen will not affect its filesize.

Professional sites, such as museums, scan an image twice: once in small size, for a small image with a small filesize that loads very fast, and a second time for a larger image that takes longer to load.

Information on resolution, image formats and file sizes – also see the pages on Graphics

Image size: The bigger the image, the slower it will load. Try 50% on your first scan of a normal size photo.

Cameras take pictures in pixels = dots.
The key measure is resolution, expressed in dots per inch, or dpi.
The higher the dpi, the greater the quality, the larger the file size.

Resolution for web use: The maximum you can get on a VGA monitor is 72 dpi (dots per inch). So do not scan at 600 dpi or higher.
Resolution for printing: This depends on your printer. 300 or 600 dpi is good; go higher if you have a color laser printer.

Color: Choose Black and White for a line drawing, Gray scale for a black and white photograph, Color for a colored photograph.

Do a preview if your software permits it, then mark the area to be scanned, then do the scan.

Scanning slides

HANDLING SLIDES AND SCANNER SURFACES: do not touch them.

The matte (rather than the shiny) side of the slide should be toward the light source because the shiny side would reflect light. The shiny side usually has printing on the holder (such as, Ektachrome Slide or Kodachrome Transparency), printed upside down, of course, as a slide projector reverses the picture. Angle the slide towards a lamp to see the difference.

Hoffmann, March 2006