I work at a newspaper that makes extensive use of postscript files generated from Quark 4.11 on a Mac G4 running OS 9.0.4. Occasionally, a postscript file will be blank. In other words, a postscript file will be created, but printing it or distilling it into a PDF file will produce a document with absolutely no image. Has anyone else experienced this? If so, where might I start to find the cause?