How To Optimize Your Variable Data Printing For Speed and Profitability

It's widely accepted that print has a central role in multi-channel marketing and that in combination with a range of digital 'touches' it can significantly raise response rates. Digital printing technologies of various kinds are now in widespread use, enabling personalised or variable data printing (VDP) so that not only is the text and image content of each piece tailored to the individual recipient, even the number of pages can be varied to suit.

Today's sophisticated multi-channel marketing automation tools are a far cry from the simple mail merge of the 1990s and earlier, or even the hybrid printing of a decade or so ago, when brochures or mailers pre-printed on offset presses could have personalised text overprinted via a digital print head.

Now, everything is printed afresh on each page. While that's no problem for toner or inkjet presses, it does potentially place a huge burden on the digital front end (DFE) and the RIP that has to drive the press. With the graphical complexity of customised pieces increasingly limited only by the designer's imagination, the processing stage in printing VDP jobs can quickly become a major productivity bottleneck.

Instead of imaging a page once for the digital press and then printing it several hundred or thousand times, there has to be an imaging process for every page, which is then printed once. Half-an-hour's delay before printing several hundred copies over a couple of hours might be acceptable, but even a minute's delay between every copy would be a productivity disaster.

Ideally, the press should be driven at its full rated speed during a VDP print run, which typically gives the RIP just fractions of a second to prepare each new page. Bad design/file construction practices can seriously impede this. Bad practices include unnecessary layering of objects and haphazard use of transparency effects, using images that are at higher resolution than is required for print, or producing vector art with unnecessarily large numbers of control points, for example.

To further complicate matters, there is no one way to create VDP jobs. There is a variety of authoring tools, ranging from simple plug-ins for popular graphic design software through to dedicated cross-media production suites that generate variable data print, email and other online assets from the same core material. With most of them it's equally possible to create VDP files that are good or bad from a printability perspective; they might - eventually - produce exactly the same print but can be better or very much worse in terms of total processing time and therefore job turnaround.

VDP 'emitters' like this also use a range of VDP 'languages' to hand off the print job to the DFE. Some are proprietary to specific hardware vendors - IBM's AFP and Xerox VIPP, for example - and some are more generalised or open, such as PPML or PDF/VT. While all of them have been developed to explicitly support variable content, some originate from the text-based transactional print world, while others are firmly aimed at graphically-driven marketing and promotional applications.

There are some important differences in the capabilities of these print formats, particularly with regard to graphics handling and especially in the level of support for advanced features such as transparency. The ability to preview the VDP print stream for checking purposes varies too: the older formats don't support any previewing at all, as the output file is assembled only at print time, while PPML jobs can be checked but only with a dedicated viewer. PDF and PDF/VT can be previewed using any PDF viewing application. Whatever DFE or RIP a printer has, it must be able to accept and process VDP files in the format that the customer or internal studio can supply.

Configurations in which VDP composition software, hand-off language, DFE/RIP and digital press are all developed and supported by the same vendor are one solution, and should guarantee compatibility and productivity but they may lack flexibility. If the entire VDP document design, database management, document construction, processing, print and finishing cycle is carried out under the printer's roof then tight integration between components ought to yield a productive solution. But what happens when a new client wants to manage their own database to generate and send differently formatted VDP files for output? What if a new campaign idea calls for graphical features in the printed material that are beyond what is currently supported?

The alternative is to look for a production system that can accept input in any of the popular VDP formats and which has the necessary power and flexibility to work productively with all of them. An ideal system would also have the ability to drive more than one make or model of digital press. This increases long-term flexibility and improves return on investment as the business grows and new speed, finishing or quality options become available.

Some level of VDP capability will be supported by just about any existing digital press installation and may provide enough functionality to begin offering VDP work to test the market. However, if VDP and multi-channel marketing are part of a more comprehensive business development plan, it's important to invest in the right production equipment for both the immediate need and for the future.