SUMMARY
Scanned images can greatly increase the amount of time and
disk space it takes to save a document. Scanned images can also affect the
amount of time it takes to print a document.
The amount of detail
recorded by the scanner is measured in dots per inch (dpi). The higher the
resolution or dpi, the more detailed the image and the larger the file size of
the image. When you are going to add a scanned image to a document, you may
want to keep the following points in mind:
- Use the optimum scanning resolution to keep images from
getting unnecessarily large. Do this by matching the scanning resolution to the
capacity of the output device.
- If the resolution of an image is greater than the
resolution a printer can print, the printer ignores the resolution that exceeds
its capacity to print.
- The best scanning resolution is equal to two times the number of dots per inch (dpi) that the printer is capable of printing.
The following table may help you select the optimum scanning
resolution.
|
| Monitor | 96 | 96 |
| Laser printer | 300 | 120 |
| Laser printer | 600 | 150 |
| Ink-jet printer | 300 | 110 |
| Dye sub printer | 300 | 125 |
| Imagesetter | 1250+ | 300 |
You may also want to consider the following "rules of
thumb."
Scan at the Appropriate Resolution
If you are scanning in color or grayscale, scan at no more than
one half the resolution of your printer. For example, if your laser printer
prints at 600 dpi, scan at no more than 300 dpi. If you are scanning in black
and white, scan at no more than your printer resolution, but make sure that
your scanner setting is "black and white" or "line art."
Scan at the Appropriate Color Depth
If your original artwork is in color, but you are printing the
image on a black-and-white printer, scan the image in grayscale. If your
original artwork is a black-and-white line diagram, scan it in black and white.
Scan at the Appropriate Size
Use your scanning program to scale the original artwork. For
example, if you are scanning a 5-by-5-inch logo to place on a business card,
use the scaling controls in your scanner software to reduce it to about
20-percent of its original size (1-by-1-inch). Then adjust the size of the
image in one of the programs listed at the beginning of this article to adjust
the logo to exactly the right size.