When the PDF is displayed on-screen, zooming in/out will effectively downsample/upsample the screen capture, causing loss of quality.
For an optimal display of screen captures (and when printing the PDF is not the primary intended use), a separate PDF ("image viewer") may be used, with a controlled default zoom level that is related to the dpi value used in FrameMaker. This default zoom level is restored, if changed, when the reader switches pages. For an example, see http://www.microtype.com/showcase/text.pdf The linked file -- http://www.microtype.com/showcase/screens.pdf -- takes into account the different display resolution of Acrobat/Reader 5 (and earlier, 72 dpi) vs. Acrobat/Reader 6 (and later, 96 dpi by default). If you open the screens.pdf file in Acrobat/Reader 6.0 or higher, it opens at 75% zoom. Display quality is the same as the original (assuming that Acrobat's default display resolution of 96 is in effect). When you change the zoom to 74%, 73%, or 76%, loss of quality is immediately visible (missing pixels or blurry areas). Magnification settings such as Fit Page or Fit Width yield unpredictable zoom levels, and therefore unpredictable display quality of screen captures. [ Another screen-optimized approach is demonstrated at http://www.microtype.com/showcase/MultimediaAsst/Jpeg_linked.pdf ] Shlomo Perets MicroType, http://www.microtype.com * ToolbarPlus Express for FrameMaker FrameMaker/Acrobat training & consulting * FrameMaker-to-Acrobat TimeSavers/Assistants