Adobe InDesign CC 2015 - Manual (Page 622)

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Printing
Last updated 6/6/2015
2 (InDesign only) To use the Lab values of a spot color rather than CMYK definitions, choose Use Standard Lab
Values For Spots.
Create an ink alias for a spot color
You can map a spot color to a different spot or process color by creating an alias. An alias is useful if a document
contains two similar spot colors when only one is required, or if it contains too many spot colors. You can see the effects
of ink aliasing in the printed output, and you see the effects on-screen if Overprint Preview mode is on.
1 In the Ink Manager, select the spot color ink you want to create an alias for.
2 Choose an option in the Ink Alias menu. The ink type icon and ink description change accordingly.
Display or output spot colors using Lab values
Some predefined spot colors, such as colors from the TOYO, PANTONE, DIC, and HKS libraries, are defined using
Lab values. For backward compatibility with previous versions of InDesign, colors from these libraries also include
CMYK definitions. Lab values, when used in conjunction with the correct device profiles, give you the most accurate
output across all devices. If color management is critical to your project, you might prefer to display, export, and print
spot colors using their Lab values. The Ink Manager option Use Standard Lab Values For Spots lets you control which
color mode InDesign uses for these predefined spot colors: Lab or CMYK. If you need the output to match earlier
versions of InDesign, you should use the CMYK equivalent values.
Note: To improve on-screen accuracy, InDesign uses the Lab values automatically if Overprint Preview is on. It also uses
Lab values when printing or exporting if you’ve selected Simulate Overprint in the Output area of either the Print or Export
Adobe PDF dialog box.
1 Choose Ink Manager in the Separations Preview panel menu.
2 Do one of the following:
• For Lab values, select Use Standard Lab Values For Spots.
• For CMYK values, deselect Use Standard Lab Values For Spots.
About halftone screen frequency
In commercial printing, continuous tone is simulated by dots (called halftone dots) printed in rows (called lines or line
screens). Lines are printed at different angles to make the rows less noticeable. The Screening menu in the Output
section of the Print dialog box displays the recommended sets of line screens in lines per inch (lpi), and resolution in
dots per inch (dpi), based on the currently selected PPD. As you select inks in the ink list, the values in the Frequency
and Angle boxes change, showing you the halftone screen frequency and angle for that ink.
A high line-screen ruling (for example, 150 lpi) spaces the dots closely together to create a finely rendered image on the
press; a low line-screen ruling (60 lpi to 85 lpi) spaces the dots farther apart to create a coarser image. The size of the
dots is also determined by the line screen. A high line-screen ruling uses small dots; a low line-screen ruling uses large
dots. The most important factor in choosing a line-screen ruling is the type of printing press your job will use. Ask your
service provider how fine a line screen its press can hold, and make your choices accordingly.