Preflight and post-flight: new rules for quality control in the print industry, Solutions!, Online Exclusives, December 2003

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Preflight and post-flight: new rules for quality control in the print industry

By Patrick Marchese, Markzware Software

Learn about the challenges our customers in the print industry face as digital printflows become the norm-and what they can do to meet those challenges.

Just more than a decade ago, CTP (computer-to-plate) and, subsequently, direct-to-press digital printing began to profoundly alter the playing field for the print and publishing industry. Since that time, the vast majority of printers have successfully completed the transition from film to digital file exchange, but with that paradigm shift came some new dilemmas.

For example, on which types of digital files should the print workflow be based? There are certainly plenty from which to choose: PostScript, EPS, PDF, CT/LW, PDF/X-1a, PDF/X-3, TIFF/IT-P1 and so on. Also, who should be responsible for creating these final exchange formats—the content creator, a prepress vendor or the printer? And what tools and best practices should be put in place to ensure file integrity and a print job’s ultimate success?

Great strides have been made by software developers to bring to market the tools needed to verify digital file integrity—regardless of the format—but there remains a lot of work to be done in the area of best practices. Merely having these tools available to the supply chain manufacturers does little to ensure that they are appropriately applied to the process, particularly when each workflow is virtually unique.

Some printers, for example, prefer their clients to supply locked-down rasterized, or RIPd, files that have been verified for completeness and integrity before they are submitted. Others prefer their clients to submit the native application files, enabling the printer to control the creation of the final RIPd files, and, of course, to pass on this processing cost to the customer.

Regardless of the methods, what all digital workflows have in common is the need for not just one but several quality-control checkpoints to maximize success rates and customer satisfaction.

Preflight to the rescue
If you poll a few commercial or publication printers, you’ll find that one of the woes they have in common is receiving problematic files from their clients. Desktop publishing tools have both advanced the print industry and complicated it. Seemingly anyone with access to a software application like QuarkXPress, Adobe InDesign or Microsoft Publisher fancies themselves a graphic artist, but it requires a high degree of skill and education to create a digital file from these applications that will actually work in the prepress and pressroom environment. Many printers profess that more than half of the files they receive from their clients are replete with errors, such as improper color space (RGB vs. CMYK) images, low-resolution graphics and text, missing fonts and incorrectly formatted trim and bleeds.

In the days of film, it was easy to catch these errors at the prepress stage; when film was generated, you could tangibly manipulate it—lay it on a light table, measure densities, find scratches, etc. But with a digital file, it’s not as simple. To manually “look inside” a file, a graphic designer or prepress operator must open it in the native application and check each and every element to ensure that all the parts are present and accounted for—and to manually do this required a great deal of time and attention to detail. This is the reason why software developers responded with file verification tools that, in a matter of minutes, can scrutinize the digital files to ensure that it’s compliant with the output specifications.

The term “preflight” has—perhaps inappropriately—been adopted en masse by the graphics arts community to generically refer to file verification at any stage in the print or multimedia workflow. But in today’s digital workflow, it is common knowledge that this process of quality controlling digital content files actually occurs (and rightfully so) at various stages in the manufacturing chain.

Markzware Software, for instance, splits the definition of file verification—the company distinguishes between the process that happens at the creative stage, during document creation within the native application file (preflighting), and the verification that must take place at the prepress phase (post-flighting), when the final file format is created and used to drive digital contract proofing, platesetting or digital printing.

Why verify digital files more than once? Some may argue that this is a blatant redundancy that digital workflow was supposed to help alleviate. The answer becomes clear when you look at a typical file exchange.

Take, for example, the workflow relationship between a magazine publisher and its printer. At the publisher, one typically finds an art director who is pulling elements (text, graphics, partial ads) from a variety of sources and compiling them into a single page within the native application—QuarkXPress, for example. The resulting file (still a native app) may be the format that is sent on to the printer. Once there, the printer may be responsible for applying things like trapping and RIPing the file to a PDF or whatever the file format they’ve chosen to drive digital proofing or platesetting.

If there are problems inherent in the file sent to the printer, several scenarios can unfold. The printer, during post-flight, detects the problems and alerts the customer. In some cases, the printer may take on the challenge of fixing the file and conducting a new proofing cycle with the customer (at the print buyer’s expense) or they may choose to bounce the file from prepress entirely and require the publisher to resubmit a new file. The cost to the print buyer is both time and money.
But had those problems been detected at the native application stage, they could have been immediately addressed by the publisher, saving both partners time and money to resolve.

Pre- and post-flight in practice
“In every … automated type of production, two basic quality checks are needed for every major task: input control, usually called preflight—when the quality of the incoming raw materials or parts are verified just to make sure the task at hand can be performed with a certain guarantee of success—and output control, or post-flight, where the result of the task is checked to see if it meets the criteria to be sent to the next stage,” explains Jan Cox, sales development manager, workflow systems, Agfa Gevaert NV.

At Cranford, NJ-based The Ad Agency, President Jeffrey Bischoff knows how important file verification is to ensuring customer satisfaction. Working mainly in popular applications like QuarkXPress, Photoshop and Illustrator, his company designs a full gamut of print media, including everything from brochures to billboard-sized marketing messages. Every file The Ad Agency creates is run through Markzware Software’s FlightCheck Collect, which gathers and verifies every element that should reside within the file, before it is forwarded on to a printer.

“Before we had software like this at our disposal,” Bischoff recalls, “checking the files was a lot more of a hassle. It’s safe to say that it’s been a savior for me, because if I send out something that’s incomplete or incorrect—even if the printer catches it on their end—who’s in trouble? Me!”

The same distinguishing terminology—preflight vs. post-flight—may also be used to categorize the software tools designed for specific workflow stages, such as creative or prepress. And the good news is that there is a healthy competition among pre- and post-flight developers that have produced applications that support virtually any file format, workflow stage and budget. There are a plethora of tools being deployed by printers and prepress suppliers to post-flight files—each appropriate to a specific workflow volume and output file formats.

About the author: Patrick Marchese is the co-founder and president of Santa Ana, CA-based Markzware Software. He can be reached for comment at

Author: Marchese, P.
Preflight and post-flight: new rules for quality control in
Preflight and post-flight: new rules for quality control in the print industry, Solutions!, Online Exclusives, December 2003

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