Adobe Creative Suite 4 Printing Guide
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On an offset press, black ink is not 100% opaque. For a more accurate simulation of black opac-
ity, enable and properly configure color management and choose to display blacks accurately
(choose Preferences > Appearance of Black, and choose Display All Blacks Accurately for on
screen display), or, if you have disabled color management (not recommended), you can choose
the Desaturate Black command from the Separations Preview panel menu. Desaturate Black
reduces the visual opacity of the black plate only (this does not affect output). Desaturate Black
is redundant (and will provide an anemic display of black objects) when color management is on
and accurate blacks are displayed.
Keep the following tips in mind as you use the Separations Preview panel:
•
CMYK plates are always listed, even if, for example, the job uses only two spot col-
ors. However, CMYK plates are not output if no colors need to be printed on them.
•
The Separations Preview panel lists all inks defined in a document, whether or not
they are actually used in the document. Consequently, it is recommended that you
delete unused spot-color swatches before viewing separations.
•
You can view the effect of converting spot colors to process and the effect of aliasing
a spot ink (see the previous “Using the Ink Manager” in this section). Both of these
options are available in the Ink Manager on the Separations Preview panel menu.
•
You can’t preview the overprinting effects of built-in trapping or Adobe In-RIP
Trapping. Separations Preview displays only the effects of overprints applied manu-
ally through the Attributes panel.
You can use the Ink Limit feature in the Separations Preview panel to see if any areas of the
document exceed a specified limit—for example, 320% for sheetfed printing. The total ink limit
depends on the press being used to run the job, the type of stock, and other factors. If only a few
small areas are highlighted in this preview, it should be no cause for alarm. But if large areas
exceed the desired total ink limit, you may have to edit graphics and other content to ensure that
their total ink value falls within the limit to prevent printing problems.
In the Separations Preview panel, choose Ink Limit from the View pop-up menu, and enter an
ink limit value. Areas in gray are within the total ink limit. Areas shown in red are over your ink
limit; more intense reds indicate greater degrees of ink-limit excess. The percentages along the
right side of the panel indicate the ink amounts at the location of the pointer.
To view the ink percentage at any point on the layout:
1. Position the mouse where you want to evaluate the ink percentages.
2. Refer to the percentages along the right side of the Separations Preview panel. Ink values for
each plate are displayed, along with the total for CMYK plates.
Note:
When viewing separations, the total CMYK ink value is displayed, but not the total com-
bined ink value for overlapping process and spot colors. Position the cursor over areas of overlap-
ping process and spot colors, and add the CMYK total value to the values displayed for spot colors.
To highlight areas exceeding a total ink coverage limit, choose Ink Limit from the Separations
Preview panel pull-down menu. Set the Ink Limit value for your press condition; areas exceeding
the limit are highlighted in red.
Overprint Preview
Overprint Preview is a View mode (View > Overprint Preview) that simulates how objects set
to overprint will appear in color-separated output (or composite output when the Simulate
Overprint option is enabled). When Overprint Preview is on, you can see underlying objects
through overprinted objects as they would appear on press. Because Overprint Preview models
ink behavior, overprinted objects that use lighter or screened inks reveal more underlying inks
during overprint preview because they actually are less opaque when printed.
Overprint Preview also gives a more realistic view of spot colors involved with certain blending
modes. In the normal, composite view, interactions between spot color objects may be mis-
leading, so make it a habit to check files by turning on Overprint Preview. Because turning on
Overprint Preview also turns on High Quality Display, you may experience a slight slowing of
performance in InDesign as a result. Consequently, you may wish to turn on Overprint Preview
to check content, and then turn it off once you have finished.
