Illustrator

Print color separations

  1. Choose File > Print.
  2. Select a printer and PPD file. To print to a file instead of a printer, select Adobe PostScript® File or Adobe PDF.
  3. Select Output on the left side of the Print dialog box.
  4. For Mode, select either Separations (Host-Based) or In‑RIP Separations.
  5. Specify an emulsion, image exposure, and printer resolution for the separations.
  6. Set options for the color plates you want to separate:

    • To disable printing of a color plate, click the printer icon  next to the color in the Document Ink Options list. Click again to restore printing for the color.

    • To convert all spot colors to process colors, so that they are printed as part of the process-color plates rather than on a separate plate, select Convert All Spot Colors To Process.

    • To convert an individual spot color to process colors, click the spot color icon  next to the color in the Document Ink Options list. A four-color process icon  appears. Click again to revert the color back to a spot color.

    • To overprint all black ink, select Overprint Black.

    • To change the screen frequency, screen angle, and shape of halftone dots for a plate, double-click the ink name. Alternatively, click the existing setting in the Document Ink Options list, and make the desired changes. Note however, that the default angles and frequencies are determined by the selected PPD file. Check with your print shop for the preferred frequency and angle before creating your own halftone screens.

      If your art contains more than one spot color, particularly interactions between two or more spot colors, assign different screen angles to each spot color.
  7. Set additional options in the Print dialog box.

    In particular, you can specify how to position, scale, and crop the artwork; set up printer’s marks and a bleed; and choose flattening settings for transparent artwork.

  8. Click Print.

Color separation modes

Illustrator supports two common PostScript workflows, or modes, for creating color separations. The main difference between the two is where separations are created—at the host computer (the system using Illustrator and the printer driver), or at the output device’s RIP (raster image processor).

In the traditional host-based, preseparated workflow, Illustrator creates PostScript data for each of the separations required for the document, and sends that information to the output device.

In the newer RIP‑based workflow, a new generation of PostScript RIPs perform color separations, trapping, and even color management at the RIP, leaving the host computer free to perform other tasks. This approach takes less time for Illustrator to generate the file, and minimizes the amount of data transmitted for any given print job. For example, instead of sending PostScript information for four or more pages to print host-based color separations, Illustrator sends the PostScript information for a single composite PostScript file for processing in the RIP.

Emulsion and image exposure

Emulsion refers to the photosensitive layer on a piece of film or paper. Up (Right Reading) means that type in the image is readable (that is, “right reading”) when the photosensitive layer is facing you. Down (Right Reading) means that type is readable when the photosensitive layer is facing away from you. Normally, images printed on paper are printed Up (Right Reading), whereas images printed on film are usually printed Down (Right Reading). Check with your print shop to determine which emulsion direction it prefers.

To tell whether you are looking at the emulsion side or the nonemulsion side (also referred to as the base), examine the final film under bright light. One side appears shinier than the other. The dull side is the emulsion side; the shiny side is the base.

Image exposure refers to whether artwork prints as a positive or negative image. Typically, print shops require negative film in the United States and positive film in Europe and Japan. If you are unsure about which image type to use, consult your print shop.