Changing the screen dithering
You can change the type of dithering used to display your document on the screen.
To change the screen dithering
1. From the Utilities menu, choose Options.
2. Click the View tab.
3. In the dithering section, choose None, Ordered or Error-diffused.
None means there will be no dithering, Ordered uses an ordered (regular) dithering pattern and Error diffusion uses diffusion dithering (a more complex dithering technique). In general, Error diffusion will give the best results, but is slower to redraw than the others. Choosing no dithering will give the fastest redraw times.
Tip
Other drawing packages use ordered dithering. If you enable error-diffused dithering your pictures generally look better than those produced with other packages.