28
Wed, Jun

Get ready for PDF 2.0

The first new version of the PDF specification since 2008 has just been published by the International Standards Organisation. So what will be the impact on print production of PDF 2.0 - the first post-Adobe standard? Martin Bailey, CTO of Global Graphics and the primary UK expert to the ISO committees working on PDF, PDF/X and PDF/VT provides pointers. 

A key requirement of PDF 2.0 is continuity for the billions of existing users, files and existing PDF tools. And the new standard has been developed in a committee comprising subject matter experts from a number of countries to make improvements that reflect real-world situations.  So, the emphasis has been on evolution not revolution, and to introduce greater clarity compared with PDF 1.7.  In fact, this will be one of the main benefits for many people because it will bring greater consistency across products and vendors.

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.

I’ve picked out a couple of instances from the PDF 2.0 specification that will be of particular interest to those of you in the wide-format sector but if you want to read more about the changes there’s a white paper that you can download for free at: http://www.globalgraphics.com/impact-of-pdf-2-0-on-print-production

More colour consistency when gang-printing

There will be a significant benefit from colour space inheritance when gang-printing. So 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.

Tweaks to transparency

The ISO PDF 1.7 standard, and all previous PDF specifications, were slightly vague about exactly when the colour space of a graphical object involved with PDF transparency needed
to be transformed into the blending colour space. The uncertainty meant that implementations from different vendors could (and sometimes did) produce very different results. Those statements have been greatly clarified in PDF 2.0 and products will be more consistent in which graphical objects must be transformed for transparency blending.

Security conscious customers

There’s a new security algorithm in PDF 2.0 using AES 256 so as soon as you add a password to a PDF 2.0 file the contents are encrypted. Any previous algorithms have been “deprecated” meaning they are out-dated and insecure and shouldn’t be used. In secure environments you need to be able to handle these files. Importantly this is one of the few areas where an older PDF reader won’t simply ignore features in a PDF 2.0 file but may error on the PDF 2.0 file and fail to continue processing.

Drivers for PDF 2.0 adoption

Accessibility has been one of the largest areas in the development of PDF 2.0. Why does this matter for print? Well, quite simply because the drive for compliance with pressure from activists, large corporates and government departments will mean that the very same files could be supplied for print.

How to approach your workflow

What are the potential risks if you don’t upgrade your workflow to be able to handle PDF 2.0 files? You should 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 (with the exception of security – see above). Old readers can’t possibly know if those new features are important to you or to your workflow. The safest approach to adoption of PDF 2.0 is therefore 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.

So when you implement PDF 2.0, I would suggest that you 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. 

Ask your current equipment vendor what will happen if you have to process a PDF 2.0 file with your existing set up and also when they plan to be shipping PDF 2.0 support in the future.