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) |
72 and up |
| Photos |
300 (use if includes text) |
150 |
100 |
72 or 96 |
-
Save your file in an uncompressed format, like BMP or TIFF. Not JPG!!! JPG is a compressed format suitable for viewing on video screens, 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!
Scanning Really Big Items
If you have something bigger to scan than the scanner window, you can try scanning in pieces and putting them together in a program like Corel PhotoPaint or Adobe Photoshop. This is tricky, and I have found that there will be distortion along the edges due to the item not being able to be completely pressed flat against the glass window. I have had good results sending large items to Mesa Reprographics in Albuquerque. Ask them if they still have a courier that picks up items on a regular basis in Socorro. I haven't had good results using photo stitching programs, but you may have better luck than me.