Dithering Removal

If you digitize a printed document (e.g. a book or magazine), you must perform a dithering removal during scanning. If not, you will see ugly dot patterns in the resulting image. These dot patterns cannot be corrected later.



Figure 6: This magazine image was scanned without dithering removal.

Almost all scanner interfaces include a dithering removal function, normally named Dithering removal or Descreening. In general, several options are available for this function. Choose the one that is best for your situation.



Figure 7: Here, three dithering removal options are offered by default and others can be configured by the user.

Finally, remember that dithering removal tends to make the resulting image slightly out of focus. Consequently, remember to inactivate dithering removal when you scan "real" photos.