About transparency support

Transparency is an effect that you can build in Adobe Illustrator 9 and later and Adobe InDesign 2 and later. When you write a PDF 1.4 file from these software applications, the file contains native transparency.
Prinergy supports transparent objects in digital masters. This transparency support should:

• Enable simpler, faster, and more accurate trapping
• Retain the number of editable objects in Acrobat
• Help to eliminate artifacts (on output, especially in low-resolution proofs) that are sometimes introduced during flattening

Differences between Prinergy versions

Prior to Prinergy 4, transparent objects in PDF 1.4 and later files had to be flattened to PDF 1.3 objects during the normalizing process. Flattening is the process of converting all overlapping transparent areas into discrete, opaque areas to represent the look of the original transparency. Flattening retains the vector integrity of the objects as much as possible; however, flattening may rasterize some objects, depending upon file complexity.
The flattening feature is available in Prinergy 4 and later by selecting Flatten to PDF 1.3 in the Normalize section of the refine process template.

Handling files with transparency

The following file formats (by their nature) do not contain native transparency:

• PS
• EPS
• DCS
• PDF 1.3 or earlier
• PDF/X-1a (PDF/X-1a is a restricted subset of PDF that prohibits transparency.)

(If the original file had contained transparency effects, they would have been flattened.) Because these formats do not include native transparency, they cannot take advantage of Prinergy 4's transparency handling.
To take advantage of Prinergy's transparency handling, ensure that your incoming files contain native (unflattened) transparency. To do this, save incoming files as PDF 1.4 or later in Illustrator and InDesign.
To determine whether a PDF file contains native transparency, open the file in Acrobat and use the Transparency Flattening tool (the location of this varies by Acrobat version). Set the Highlight list to Transparent Objects. If any objects in the preview appear in red, there is native transparency in the file.
You can preserve transparency during the refine process. The PDF 1.4 to PDF 1.6 (Acrobat 5 to 7) list on the Normalize pane in the refine process template has the following options:

• Flatten to PDF 1.3: Prinergy detects and flattens all files with native PDF 1.4 transparency, using the highest quality setting. This is the behavior from Prinergy 3 and earlier.
• Leave as is: Prinergy detects and preserves transparent effects in PDF 1.4 or later files.
• Fail: Prinergy detects but fails when it encounters transparent objects.

Processing transparent files: possible approaches