Due to the many options available to PDF document authors, it’s no longer appropriate to say, ‘Looks like a job for PDF!’ It’s now more important to know which PDF.
An event coordinator at a publishing conference once told me that, eventually, ‘Running a PDF conference is going to be like putting on a floppy disk show.’ Technology has evolved since then, with the increasing proliferation of CD and DVD burning capabilities, but the point remains: once PDF creation and manipulation capabilities are truly ubiquitous and the format can store pretty much anything that pops into your head, won’t evangelizing the technology a tad redundant? Perhaps, but education will always have a place with PDF.
As I mentioned last week, PDF is a powerful and flexible format. I suggested in that column that the question is whether this flexibility could ultimately prove to be its downfall. After all, what use is the best technology in the world if no-one knows how to use it effectively? This is particularly important in areas where a given PDF document can be touched-up or processed by many different hands.
In the print workflow, for instance, any errors in the process can be inherited by later stages. If each phase (e.g. design & PDF creation, prepress and printing) were to add just one or two small errors, then the final document could print in a way that is very different from the author’s intent. In response to this need, the PDF/X (the ‘X’ is for eXchange, geddit?) family of standards was developed. These standards aim to keep the files as simple as possible, cutting out interactive elements like bookmarks and multimedia, ensure that colors are defined using a print color space (CMYK or spot) rather than an on-screen one like RGB. In fact, they even mandate the versions of PDF that can be used in order to avoid issues caused by the latest features.
With documents designed for viewing online, the requirements aren’t as strict, but make reading the documents far more pleasant and intuitive. Here are a few pointers:
- Bookmarks: Adding these to any document designed to be read online should be standard operating procedure. When you create a PDF document using the PDF Maker Word macros that ships with Acrobat. They can also be created simply from within Acrobat.
- Hyperlinked tables of contents: These act as document roadmaps, and again, their addition should be standard operating procedure.
- Links: These are analogous to web hyperlinks, and can link to web pages, other files, or even other PDF documents. One way to ease the download pain for users with slow internet connections is to split a document into chapters that link to one another, to ensure that a user only downloads what they need. It’s also possible to build a single document, complete with internal links and bookmarks, and split it, automatically redirecting the interactive features to the split documents with ARTS PDF Split and Merge Plus.
- Optimization/linearization: This allows byte-serving, and enables users to download only the page they are attempting to view. A must for online documents.
- Searchability: This might sound like a no-brainer. I mean, PDF is an electronic document format, right? Well, if the PDF was the result of a scan, that may mean that the text is actually just a picture of text. Scanning a document is like taking a digital photograph of it — while you can see that its contents are text, the document is just pixels as far your computer is concerned. What you’ll need is to run it through an Optical Character Recognition (OCR) tool, which will compare the shapes on the page with a database of known characters, adding an invisible layer of searchable text to the document.
- Security: Make sure that you have an appropriate level of security. People often mistake capability for imperative here. While Acrobat 7 allows a high level of granularity and power in terms of security, you rarely need to enable any but the most basic options for public documents. For instance, if you have a free document, say, PDF product documentation, you may want to restrict changes to the document maintain the content’s fidelity, but you probably don’t want to require users to know a password just to open the manual.
I’ve only addressed two uses of PDF in this piece, but you can already see how greatly the requirements of the PDF files vary between the two. The next time you create a PDF file, ask yourself three questions:
- Who is the document’s intended audience? (e.g. all web site visitors, printers, or personnel who have signed an NDA.)
- Where are you sending, posting or filing it? (e.g. prepress house, company web site, or corporate intranet.)
- What objects are contained in the PDF? (e.g. text, graphics, multimedia.)
- How will your intended audience use the document? (e.g. copying/quoting text, forwarding by email, reviewing, updating or fixing the file.)
Until next time, happy PDF creation!
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