In Calamus documents you can assign completely different rasters
to individual pages or even individual frames. This is not so simple
in PostScript and is not supported by PostScript export in Bridge. If
you require special raster types for individual frames, we recommend
therefore that you pre-rasterize them with the Bridge module
Convert function of the
C M Y K (4 frames), Monochrome. This raster image data is then exported quite normally by Bridge with any other data and will not be rasterized further by external PostScript RIPs.