User Guide

Chapter 12398
Note: If you have specified overprinting options for selected objects, these
object-level overrides are not indicated in the Separations Colors window. For
more information, see “Overprinting” on page 405.
9 In the Angle column, click to display the Screen Angle dialog box and enter an
angle value in degrees, then click OK.
10 For Halftone Screen, choose an option from the pop-up menu to display
optimized screen ruling (lpi) and resolution (dpi) settings from the selected
PPD file. If the selected PPD supports custom screen settings, choose Other
and enter custom lpi and dpi settings, then click OK.
Note: You can also apply halftone settings to selected objects. For more information,
see “Applying halftone settings to selected objects” on page 399.
11 Select Override Objects to override halftone screen settings you have applied to
selected objects, for the current print session only (the object-level settings are
preserved in the document and can be used for future printing sessions).
12 For Transfer Function, choose an option for modifying the way gray levels are
interpreted by the PPD:
• Choose Unadjusted to make no change to gray levels.
• Choose Normalize to print gray levels that transition smoothly from 0% to
100% black. This option is intended for use with a PPD that includes its own
Normalize function.
• Choose Posterize to print four levels of gray. This option is intended for use
with black-and-white printers.
13 For Spread Size, choose an option from the pop-up menu or enter a value in
points for controlling the amount that basic strokes and fills can expand during
printing. Use Spread Size to compensate for misregistration.
14 Enter other options in the Print Setup dialog box, or click OK.
About screen ruling
Screen ruling, measured in lines per inch (lpi), is the number of lines or rows of
halftone dots printed per inch on the page. A high screen ruling prints the dots
close together, creating sharp, distinct colors and images. A low screen ruling
prints the dots farther apart, creating a coarser effect.
Image resolution, measured in pixels or dots per inch (dpi), is the number of
pixels displayed per inch of printed length of an image. An image with a high
resolution contains more pixels per inch and therefore has more detail.
The relationship between image resolution and screen ruling determines the
appearance of detail in a printed document. In general, the higher the image
resolution is, the higher the screen frequency you should use for printing.