Achieving Reliable Print Output from Adobe ... - Adobe Partners

Artifacts on the margins
This graphic shows how adjoining atomic regions
can, under certain circumstances, exhibit differences
in appearance, sometimes known as stitching artifacts.
Font conversion during flattening
If text is involved in transparency, the Flattener often needs to rasterize or outline some of the
glyphs in the text. The Flattener uses the font information contained in the font files that are
present on the computer where the flattening is taking place. Because the Flattener only flattens
text in areas affected by transparency, it’s possible that some glyphs will be flattened while others
remain unaffected. In most instances, you will not be able to detect a difference between the flattened
and normal text in the final output.
As illustrated in the following graphic, in some cases, the Flattener must convert portions of text
to outlines as in the case of text that is beneath a drop shadow (left). Note in the wire-frame view
(right) that the Flattener has outlined a portion of the text, but a portion remains rendered as a
font. The difference in the way the characters are created can cause visible differences in apparent
weight because the outlined text does not have PostScript font hinting applied. In such cases,
by selecting the Convert All Text to Outlines flattener option, you can help make all of the text
uniform in weight.
Text converted to outlines by the Flattener
The Flattener has outlined a portion of the text that
appears under a drop shadow, but a portion remains
rendered as a font.
Host and RIP font mismatch
In some situations, a font loaded on your computer is replaced by a similar font that is loaded
on a printer’s RIP. For example, the font Helvetica is one of the standard fonts that is included
in all PostScript RIPs. In the PostScript printer description file (PPD) for a PostScript printer,
Helvetica is listed as being resident in the printer. When you print a job in which you use
Helvetica, the PostScript file generated by the application will not include the version of
Helvetica on your local system—the RIP’s version is used instead. If the version of a font in the
RIP differs from the version used on your computer, the flattened text may look different than
the text the RIP printed by using its version of the font. When printing from InDesign 2 or CS,
you can avoid this issue by choosing Download PPD Fonts in the Graphics panel of the Print
dialog box.
Color management during flattening
If you use color management in your workflow, colors involved in transparency may be transformed
earlier than you expected and may not match the actual press conditions after being flattened.
In applications like Illustrator CS, this transformation can happen if you haven’t correctly
chosen the working space profile for the document. In InDesign CS—which supports working in
multiple color spaces—the transparency blending space must also be properly set.
Conversion of spot colors
Certain blending modes, such as Difference, Exclusion, Saturation, and Luminosity, can introduce
unexpected process colors or convert spot colors to process. Be sure to use the Separation
Preview available in InDesign CS and Acrobat 6 Professional to confirm your expectations prior
to output.
Achieving reliable print output from Adobe
applications when using transparency
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