Scanning Tips
by Susan Delap
These tips apply to flatbed scanners.
- Before scanning photos, blow dust off them with a can of compressed air.
- If the scanner window is dirty, ask the Staff Engineer how to clean it. I use distilled water and a soft tissue--lint free would be better if you have it.
- If scanning double-sided items, writing from the reverse side may show up as a ghost image. Place a black piece of paper behind the paper to prevent this.
- Lift paper off the scanner window with another sheet of paper to prevent getting fingerprints on the window
- Be careful when selecting the type of document. If it isn't color, don't scan it in color (RGB) or the file size will be much larger than it needs to be. Here is a guide:
- Line art for B&W documents with no gray scale
- B&W Photo for anything B&W with gray scale
- 256 colors (RGB) for anything with color
- CMYK colors ONLY if you are sending to a commercial printer who requires CMYK color
- Select the proper resolution (see table below).
- Scan all your images at print quality resolution unless
you know you will never need to print the image. This way you only have
to scan something once. You can always resample an image at a lower resolution
to fit a lower quality application, but you can't go the other way.
Scanning Resolution Guide
(Units are in dots per inch (dpi) and apply to the final size (target) of the scanned image |
| Scan Type |
Best |
Okay |
Fair |
Web |
| Line Art |
600 |
300 |
200 (FAX quality) |
110* |
| Photos |
300 (use if includes text) |
150 |
100 |
110* |
*Although 72 dpi is still the web standard, photos at this resolution look pixelated on LCD monitors. Photos at 110 dpi look better.
-
Save your original scan in an uncompressed format, like BMP or TIFF. Not JPG!!! JPG is a compressed format suitable for viewing on computer monitors, not for printed output. You can always create a compressed, lower version JPG from your original high-quality TIFF or BMP, but not vice versa! Don't save your files in Word or PowerPoint files. You usually have to shrink them to get them to fit on the page, and this makes it hard to extract the graphic at the original size and resolution.
Scanning Really Big Items
If you have something bigger to scan than the scanner window, you can try scanning in pieces and using a stitching program (I prefer Corel PhotoPaint.) This can be tricky because there will be distortion along the edges due to the item not being able to be pressed flat completely against the glass window.
The Lanier copier in the office can scan images up to 11" x 17". The Bureau has a large format scanner--at least 36"' wide. See Mark Mansell at x5562.