News Analysis: Second of two parts: PDFzone gets an inside look at how Adobe tests new versions of Acrobat and Reader and what happens when an incompatibility issue comes up.Ed. Note: The first part of this article may be found here.
In Adobe co-founder John Warnock's electronic-document Camelot—the original code name for Acrobat—people would open, view, and print any PDF using the utility that became known as Reader. Any PDF made from Day One would look just like the original on screen or paper.
That's the Camelot that everyone—including national, state, and local governments and their constituent agencies—buys into when standardizing on PDF as an official electronic document format.
Camelot's just an ideal, perhaps a mythical impossibility. On good days, when everything's working right, it feels as though you're there, which lulls many users into taking Acrobat and Reader's solid performance for granted and expecting perfection.
Perhaps if Adobe took everything in-house, hid the PDF spec from the developer public and didn't allow other people to make PDF-creation tools, the company might retain tighter control on bugs and inconsistencies.
But Adobe hasn't done that: Third-party PDF writers, filters, and widgets are the grease in the giant machine of PDF proliferation. PDFs are everywhere for the simple reason that you don't have to spend hundreds of dollars for Acrobat, the Cadillac app, to make them.
Yet Adobe Acrobat and Reader must still attempt to support all PDFs, no matter where they come from—even from Adobe's own tools dating back to the days when dinosaurs roamed the earth (1993). Even when those PDFs contain error-ridden fonts of unknown origin.
That particular problem caused consternation for a PDFzone reader who works for a large publishing company. He found that some of the 6,500 technical documents his company built with Acrobat Distiller 3.0.2 in the 1990s no longer properly opened in Acrobat and Reader 7. Files that worked for years suddenly threw up a font error dialog, and math characters didn't display properly, rendering the documents incomprehensible.
Reality for Adobe represents compromises here and there. Tightening up tolerances in favor of a more stable system can take us further from Camelot. That's what happened here: Adobe deemed that particular font error to be something that Acrobat and Reader could no longer let slip by.
"We make every effort possible to not break older PDF files. . . . We even go so far as to sometimes make corrections for other [vendors'] mistakes in PDF creation," said David Stromfeld, Acrobat product manager. "We recognize that the number of files out there is immense, that businesses rely on those files. We go through extraordinary measures to make sure we are aware of the files that are out there and make sure we don't do anything that affects them."
Adobe's pre-release testing for Acrobat and Reader includes not only an external group of beta testers, but also an internal gauntlet of hundreds of thousands of test PDFs. Many of these files earned their spot in "the suite"—as Stromfeld calls it—because they contain nettlesome features that in the past exposed weaknesses in newly minted code.
That means that sometimes, Adobe engineers arrive at forks in the road: Go one way, and X number of PDFs might not open quite right in the next Reader. Take the other fork, and Acrobat and Reader might crash upon encountering an ancient PDF with a flaw that used to be harmless but now is offensive to an underlying operating system, security feature, or other new bit of code.
Taking either fork, sometimes, seems to jilt some group of users and violate Warnock's directive that Reader be inclusive and maintain perfect graphic fidelity. That means, of the likely billions of PDFs out there, some of them probably won't open in Reader forever.
Minimizing the odds of that happening, industry consortiums are working on standards such as PDF/A (ISO 19005-1, for document archiving) to create archival PDFs that might seem vanilla compared with the latest and greatest files pushing the boundaries of multimedia technology, but that are much more stable.
For our guy's 6,500 PDFs, all's well that ends well: Adobe pledged to work out the font problem in some future release of Acrobat and Reader, be it the next rev or an updater. His files go in "the suite."
"In an upcoming release, we will be addressing this issue, and this dialog will no longer appear," Stromfeld says. "This particular issue slipped through our cracks. We made the change with the best of intentions—to reduce instability—but in talking to customers going back to 2005, we realized it affected a higher volume of files than [we thought]."
Our protagonist won big. No doubt the name of his company helped his cause, as well as the amount of international business, Acrobat seats, and PDF proliferation his company and its customer base represented. But what about all the other people who encounter errors that never came up before when new versions of Reader come out?
"Any time a customer raises an issue like this, we take it very seriously," Stromfeld said. "We definitely take a look at the details of what's going on and make every effort to make sure there aren't cases where future versions of an Adobe PDF viewer affect the population of PDF files that are out there."
That doesn't mean Adobe will issue a patch for every problem PDF. Or that they'll ever take us to Camelot. But in watching this story unfold, it does appear like they're making a good-faith effort to try.
Document Management 
