Apple Express Fax/Modem - Manual (Page 85)

Depending on the content of the received fax, you can experiment with the
monitor settings and the Use Smoothing command to get the best resolution
for display. Smoothing is enabled by default.
2 Choose Use Smoothing from the Page menu.
How smoothing works
The resolution of a fax is 200 dots per inch (dpi). Your
Macintosh converts the 200 dpi fax resolution to the 72 dpi of
the Macintosh screen. The conversion process concentrates gray
areas together, making the document appear darker. The
smoothing feature looks for dark areas, and then applies a
special algorithm known as dithering to improve document
resolution.
73 F A X V I E W E R