Previewing separations, transparency, and overprints
Use the Separations Preview palette to evaluate on screen how a document will color-separate on printed output. You can view individual spot and process color plates or any combination of plates. If you need to make adjustments, you can do so with immediate feedback by editing while separations preview is in effect.
Adobe InDesign previews separations by displaying any combination of the inks defined in the document, such as the cyan plate and the magenta plate. The results display to the monitor using
InDesign’s high-resolution screen display engine, employing transparency where necessary to represent conditions such as overprinting, RGB-to-CMYK conversion, and spot color interactions with transparency. However, trapping is not simulated. The ability to display overprints and ink limits for any combination of plates can make the separations preview capability more useful for evaluation than a laser-printed separations proof. Separations preview is calculated using the ink characteristics for process and spot inks.
On a press, black ink is not 100% opaque. However, when color management is disabled for an
Adobe InDesign document, Black displays on-screen as 100% opaque. This display is not a useful simulation when evaluating how Black interacts with other colors, such as in areas where a rich black is applied. For a more accurate simulation of Black opacity, you can enable and properly configure color management, or you can choose the Desaturate Black command from the
Separations Preview palette menu. Desaturate Black reduces the opacity of the Black plate only.
Desaturate Black is disabled and turned off when color management is on, because simulating
Black opacity is part of the function of color management.
Keep the following tips in mind as you use the Separations Preview palette:
• CMYK plates are always listed even if the job uses only two spot colors. However, CMYK plates are not output if no colors need to be printed on them.
• The Separations Preview palette lists all inks defined in a document, whether or not they are actually used in the document. If you suspect that unused inks are being displayed, choose Select All Unused from the Swatches palette menu and examine the selected swatches
(remember that swatch icons can indicate what kind of color it is, such as a spot). If you want to reduce the number of inks in use, you have two alternatives. You can use the Ink Manager to alias any ink to another ink, or you can delete swatches in the Swatches palette, such as those that the Select All Unused command selects. However, the Ink Manager method has the advantage of not altering the customer’s file. After using either method, you can evaluate the results using the Separations Preview palette.
• You can view the effect of converting spot colors to process and the effect of aliasing a spot ink. Both of these options are available in the Ink Manager on the Separations Preview palette menu. For example, if a customer used three green spot colors where the job specified only one, and you use the Ink Manager to assign the extra green spot colors to a single spot or process plate, the screen will correctly show the ink aliasing you’ve applied. For more information, see
“Ink Manager” on page 87.
• 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 manually through the Attributes palette or by applying transparency.
• You may want to disallow display performance overrides applied to individual graphics. When you use Overprint Preview, Adobe InDesign uses High Quality Display mode to show graphics at high resolution, except for graphics that have their own display performance settings.
To display the Separations Preview palette:
Choose Window > Output Preview > Separations.
To remove unused colors (so extra inks won’t appear in the Separations Preview palette):
In the Swatches palette, choose Select All Unused, and then click the Delete Swatch icon
(trash can).
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To preview separations:
1 In the Separations Preview palette, choose Separations from the View pop-up menu.
2 View any combination of separations by clicking eye icons to hide or show plates. Clicking the
CMYK eye icon shows all CMYK plates.
To preview areas that are over your ink limit:
In the Separations Preview palette, choose Ink Limit from the View pop-up menu, and enter an ink limit value.
Areas in red are over your ink limit, and areas with more saturated reds are further over the ink limit. Areas in gray are within the ink limit.
Red areas indicate areas over the specified Ink Limit in the Separations Preview palette, and the percentages along the right side of the palette indicate the ink amounts at the location of the pointer.
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