A summary of the changes that will affect print production following the publication of a new international standard for PDF can be found in a white paper just published by Global Graphics Software. ‘The impact of PDF 2.0 on print production’ provides background information on the new standard, insight into what it means for print, and recommendations around implementation planning.
Global Graphics CTO Martin Bailey, the white paper’s author, is the primary UK expert to the ISO committees working on PDF, PDF/X and PDF/VT. He said: “When it is published [this month] the new ISO standard will define PDF 2.0, and will replace PDF 1.7 over time. It’s been developed in a committee comprising subject matter experts from many countries. The overall aim is to make improvements that reflect real-world workflows and factor in updates that will help to futureproof working procedures.
“But print service providers, graphic designers, press vendors, PDF application developers all need to be aware that older PDF readers will silently ignore some aspects of the new specification and won’t know anything about any new features in the file. Old readers can’t possibly know if those new features are important to you or to your workflow. So the safest approach to adoption of PDF 2.0 is to ensure that all applications and tools that consume PDF are upgraded to support PDF 2.0 before you start thinking about upgrading the file creators.
“My best advice is to start at the back end of your workflow - probably the Rip, or DFE, or an integrated prepress workflow - and work upstream. That way you’ll never be trying to consume PDF 2.0 in a product that doesn’t really know what to do with it.
“The PDF committee has also worked hard to clarify text carried over from the existing PDF standard. As an example, imagine a specification that says that you should drive west out of a city on a specific highway. Most people around the world would drive out on the right side of the highway, because they drive on the right in their own countries. A few would drive out on the left side of the highway. Both would be correct according to the specification. In PDF 2.0 many vaguely worded cases like this have been identified and made clearer so that products from all vendors will do the same thing; we’ll all be driving on the same side of the road.”
The white paper clearly outlines risk areas and makes several recommendations as to how to introduce PDF 2.0 into a print workflow.
In a nutshell the main changes affect:
- Colour and output intents:
The printing condition for which a job is created can be encapsulated in professional print production jobs by specifying an ‘output intent’ in the PDF file. PDF 2.0 allows separate output intents to be included for every page individually. The goal is to support jobs where different media are used for various pages, e.g. for the first sheet for each recipient of a transactional print job, or for the cover of a saddle-stitched book. In PDF 2.0 it’s also now possible to embed spectral measurement data for spot colors.
- PDF transparency:
PDF 2.0 includes a number of changes around transparency, driven by what has been learnt about where the previous PDF standards could trip people up in real- world jobs. It will now be much easier to get the correct colour when imposing multiple PDF files from different sources together. That’s especially the case when you’re imposing PDF/X files that use different profiles in their output intents, even though they may all be intended for the same target printing condition. The obvious examples of this kind of use case are placing display advertising for publications, or imposing for gang-printing.
- Halftones:
Halftoning and screening are often thought of as completely understood and stable, but there were still a number of issues identified in real-world print environments that will benefit from changes in PDF 2.0.
PDF 2.0 allows a single file to be created that can be used in a variety of Rips that support different sets of proprietary halftones and to select the best one available in each Rip for that specific object. This functionality is expected to be used mainly for high-quality flexo press work, where it’s a key part of the workflow to specify which halftone should be used for each graphical element.
- PDF developers can join interoperability workshops
As well as providing a white paper, Global Graphics will be hosting two PDF interoperability workshops on behalf of the PDF Association. The goal of these events is to provide a platform for PDF tool developers to validate their work against the ISO 32000-2 (PDF 2.0) standard by working with vendors of other tools. They are open to all PDF developers and are free of charge.
You can download a copy of the white paper at: http://www.globalgraphics.com/impact-of-pdf-2-0-on-print-production