Change the entry in the color file (colr directory) for values outside
the
masked area (0=no data) from white (255) to black (0). For version 4.1
color files either change the entry 0:255 (or maybe 0:255:255:255) to
0:0, or if there's no entry for 0 values add the entry 0:0.
Note: The color files have changed in 4.1, however it doesn't appear
to
me that the maps in the spearfish/PERMANENT mapset have been
consistently
updated, so using these for examples may be misleading/confusing.
Happy color twiddling,
Andrew Hertz
hertz@geog.psu.edu