Set up your Color Manager settings to color manage any imported vector EPS or PDF files. To do so:
- Go to QuarkXPress > Preferences and click on the Color Manager pane.
- Select the Color Manage Vector EPS/PDF and Include Existing Vector EPS/PDF in Layout checkboxes.
- Click OK,
- Export your layout as PDF, ensuring that you have selected the Grayscale Color Setup.
Because EPS and PDF files are encapsulated color files, QuarkXPress needs to execute a color transform to a grayscale color space for these imported images. You can set Quark Color Manager to manage vector EPS and PDF files.