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if possible. Additional information about handling Illustrator 9 or later files containing
transparency is available at the Adobe web site (www.adobe.com).
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Blend modes.
As in Photoshop, blend modes are a form of transparency that affect how over-
lapping layers visually combine. Adobe InDesign properly handles spot color and transpar-
ency in most situations. However, if the Difference, Exclusion, Hue, Color, Saturation, or
Luminosity blending modes are used with transparent objects that interact with spot colors,
use the Separations Preview palette to monitor the results more accurately, or achieve the
effect using other blending modes or techniques. Using these blend modes with spot colors
won’t convert them to process colors, but the nature of these blending modes makes them
harder to use with spot colors.
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OPI workflows.
Specific steps must be taken to ensure that high-resolution data is present
for images that will be handled with an OPI workflow, because flattening occurs before the
generation of PostScript. See “Flattening OPI workflows” on page 55.
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Pre-separated image data, such as DCS or multitone files.
Colors in these files are already
assigned to plates, which can be an impediment to flattening. However, transparency is not a
problem for most Photoshop DCS 2.0 files because Adobe InDesign CS can recombine their
plates, integrate them into a layout containing transparent objects, and then re-separate
them. For recommendations on using transparency with files saved in pre-separated formats
other than Photoshop DCS 2.0 format, see “Flattening DCS workflows” on page 55.
•
Color management.
If color management is in use it will also affect any color conversions
resulting from transparency. This is another reason color management settings must be
synchronized with the customer and appropriate for the current workflow; otherwise
transparency may result in unexpected colors. Be sure the document’s working color space
is set to your intended output device before output. This ensures that transparent objects are
assigned suitable in-gamut colors during flattening.
•
Partially flattened text.
When using the Flattening Preview palette, choose Outlined Text
from the Highlight pop-up menu to watch how text areas become flattened. If highlighting
indicates that some, but not all, characters in a text frame are converted to outlines, the text
may appear inconsistent when output. This may happen if a text frame intersects multiple
transparent objects in a way that causes different flattening results across the characters
in the text block. For these areas, consider applying a customized flattener preset where
the Convert All Text to Outlines option is on. This ensures that the text appears consistent
across all flattened areas, though small type may appear to be slightly thicker.
Summary
While being in communication with the customer is good practice, it’s especially critical
when working with transparency. By helping customers recognize potential trouble spots
with transparency, jobs with transparency can move more smoothly through your shop. See
