This unit explains how to turn a PDF file containing a brochure into a print ready PDF that can be output on a digital printing machine or printing press. Several aspects of inspection and optimization are highlighted.
Launch callas pdfToolbox
Open the sample file "Adobe History.pdf"
First page in sample document now open
Second page has facing pages (reader spreads)
Third page as well has facing pages (reader spreads)
Open Switchboard
Click on "Arrange" button to navigate to the "Arrange" group of actions
Click on the button "Split in half"
Execute "Split in half"
Review pages in sample PDF
Second and following pages have been turned into single pages
Second and following pages have been turned into single pages
Double check the quality of separations
Visual inspection mode – Various views of process separations
"Visualize process separations" opens showing only the Cyan, Magenta and Yellow channels
All the black text seems to also show up on the CMY color plates. This is not ideal and causes several problems:
- Text will look fuzzy in the printed result
- Especially on digital presses, color ink is substantially more expensive than black ink
For optimal print results, black text should only occur on the black separation.
Inspect the black separation
Inspect all four color process separations while hiding spot colors
Showing the page image with all process and spot colorants showing
Adjust black text such that it uses only the black separation – Go to Switchboard
Go to "Colors" group and then click on "Correct 4c Black" button
Execute "Correct 4c Black" action
Correcting the four color black may take a few seconds...
Return to visual Inspection mode for process separations
Display the CMY separations
The black text is now gone from the Cyan, Magenta and Yellow separations.
Inspecting the Black separation
All the text is now only showing on the Black separation, increasing the quality of the output for text as well as reducing the cost for color ink on digital printing devices.
Switch from "Process separations" to "Spot color separations"
Inspect which spot colors are present by viewing "Spot color channels"
Seemingly only one spot color, the Adobe Red, is used here.
Inspect how spot colors and black interact by switching to "Spot color + K channels"
Check non-spot color separations
Sometimes PDFs contain a special color both as a spot color and as a process color. When processing or printing such PDFs, special colors that are expected to look the same will often look slightly different.
Regular page view with all separations showing
Change the appearance of a spot color – Go to the Switchboard
Go to the "Colors" group and then click on the "Spot colors" action
"Spot colors" action shows one spot color and allows for various changes
Modify the CMYK values so they provide a deep purple (30/100/0/50), then click execute
All "Adobe Red" objects are changed to deep purple
Visualize critical areas at the page border – Choose "Visualize safety zone"
Inspect the Trim area for objects that are too close to the border
Switch from "Page border" view to "Bleed area" view
Inspect bleed – Objects ending at trim area should rather extend into bleed area
Adjust bleed area – Go to Switchboard
Go to "Pages" group and click on "Create bleed" button
Choose values for bleed to be added and maximum anamorphic scaling
In sheet fed printing, in most cases it will be sufficient to add 1.5 mm of bleed. Some online print portals even limit the amount of bleed to such a small value to optimize sheet usage. For demonstration purposes, we choose 3 mm to show the effect more clearly.
In cases where objects are already relatively close to the trim area, it is preferable to only use smaller bleed values.