Glossary for Geospatial Science

print-raster object:� A raster that contains a dot-by-dot representation of a color print page that is viewable and can be manipulated in the TNT products like any other raster object.� Print rasters are either 4-bit (dithered) or 24-bit (undithered).� Each cell in a dithered print-raster object is a nibble (1/2 a byte or 4 bits), which can specify 16 data levels.� The 8 values currently used define one color composite dot on the printed page.� Printers create each color composite dot from dots of cyan, magenta, and yellow (and possibly black) or red, green, and blue (and possibly black).� Combinations of the three colors together with black and white are specified by each nibble�s 8 possible data levels.

You may want to create print rasters when you are planning additional modifications of the raster or you want to be able to view it before printing.� You specify the desired printer at the time you print a print raster (Main/Print From/Print-Raster).