Archive for February, 2007

Difference in margins when printing PDF documents

A member of the NDLTD (Networked Digital Library of Theses and Dissertations) email list posted the the following message last week regarding Electronic Theses and Dissertations from their students:

I have had 3 or 4 students over the last couple of months who have reported that their margin specifications have NOT been retained when they convert their ETD from Word to PDF. Our Grad School has rejected the documents, and the students are confused because Word shows that their margins should have been correct.
I just created a dummy document and printed a page in Word then converted to PDF and printed that. (I have Acrobat 7 Professional). The margins on the printed pages were different by a quarter inch.
Has anyone else had a problem with this and have you found a solution?

The margins in this case weren’t changing on conversion from DOC to PDF, but when the PDF was printed. Acrobat and Reader may scale pages on printing, depending on the printer and print driver. Make sure you choose “None” from the “Page Scaling:” drop-down list in Acrobat or Reader’s Print dialog box. The setting is sticky so if you set it once it should remain that way until you change it again.

By default, Acrobat and Reader will use one of the scaling options to make sure all the page content fits in to the printable area of a page. A PDF file is inherently scalable, and need not have white margins (a color brochure, for example). Also some desktop printers don’t print all the way to the edges of the page. Hence the page scaling options.

The screen shot below is from Acrobat 8 Professional on Mac OS X. Windows and earlier versions of Acrobat and Reader may have slightly different options, but the main page scaling options are there.

Image showing Page Scaling options in Acrobat 8 Professional for Mac Print dialog

If you ever come across printing problems like this one, then use Adobe’s online support knowledge base first (you DO check there, don’t you?). Search for "troubleshoot printing" on the support pages at For example, here is one for Troubleshooting Printing Problems in Acrobat 8 on Mac OS X.

The scenario and solution I write about above is just one possibility: there are others as you’ll see if look through the troubleshooting technical notes. I am happy to report that this particular issue was addressed by my answer, and it has not deterred the school from using PDF as the format for sharing and archiving electronic documents that must be viewed on screen and in print, both now and in the future.

Optimizing Scanned Pages: Part 1

On a recent visit to my alma mater for some Acrobat workshops I was giving, a member of the campus’ own training team asked me how to get smaller file sizes for their scanned documents when using Acrobat to convert them to image-only PDF’s. They found that the resulting PDF files weren’t that much smaller than the original monochrome (black-and-white) TIFF files. They have a lot of older how-to’s, tutorials and other learning materials that exist as paper. They now need to make them available electronically for anytime access and posterity, and to just get rid of all that paper! When Acrobat 8 was used, the results were the same.

By default, Acrobat uses a compression method called CCITT Group 4 for monochrome images in PDF. This is an old protocol developed for faxing, but works in Acrobat and Acrobat Reader 3.0 and higher. However, a newer compression method has been available since Acrobat 5.0 for monochrome images such as blank-and-white scans. It’s called JBIG2 (Joint Bi-level Image Experts Group) and offers compression orders-of-magnitude greater than can be achieved with CCITT G4. It supports both lossless compression (a la ZIP) and lossy compression (a la JPEG), the latter resulting in even smaller file sizes but at a cost of possible reduction in the quality of image.

However, it’s not enabled in the default Acrobat preferences for conversion to PDF. Here’s how you can change that.

  1. Choose Edit > Preferences… (Windows) or Acrobat > Preferences… (Mac).
  2. Select the "Convert to PDF" category on the left to open the conversion preferences.

Screen shot of Convert to PDF Acrobat Preferences

  1. From the list of file formats that your version of Acrobat can convert to PDF "directly", choose TIFF. The current settings for conversion from TIFF to PDF are listed to the right. If your list shows "Monochrome Compression: CCITT G4" then click the "Edit Settings…" button.
  2. In the Adobe PDF Settings dialog box that opens, change the Monochrome Compression setting from "CCITT G4" to "JBIG2 (Lossless)" or "JBIG2 (Lossy)". Again, the latter will give the smallest file sizes but slightly reduce the quality of the scanned image. Click OK.

  1. Click OK to close the Preferences dialog box.

Now when you open a TIFF file in Acrobat (for example, choose File > Create PDF > From File…) the resulting PDF will be using JBIG2 compression. Save the PDF file, compare it to the original TIFF files, and you should see that they are taking up significantly less space. When we tried this with the training team’s scans and JBIG2 (Lossy) compression, we saw PDF file sizes a quarter of what they originally were as TIFF. If only ROI was measured in bits and bytes!

Note that when you create a PDF file from a scanner, JBIG2 is now used as the default compression method.

There are other ways you can optimize your scanned documents, whether you scan them ahead of time, directly in to PDF with Acrobat and when running Acrobat’s built-in OCR (Optical Character Recognition). I’ll follow up with those tips for optimization another time.

Instructional Material Accessibility Standards

An instructional technology specialist in New Jersey recently pointed out to me an accessibility standard for state textbooks in the United States called NIMAS or National Instructional Materials Accessibility Standard. Information can be obtained from the American Foundation for the Blind and the Center for Applied Special Technology. "One of the great things about standards, is that there are so many to choose from!" said a wise and witty individual once-upon-a-time. How true that is! The first thing that I wanted to find out was how did this standard differ from what the US Section 508 law requires, and the W3C’s Web Content Accessibility Guidelines already offer?

This particular requirement is impacting textbook publishers first and foremost, as well as the state and local departments of education, as set forth by the US Individuals with Disabilities Education Act of 2004 (IDEA). The main part of the standard is that it provides a common, XML-based file format for textbooks and other instructional materials, so that they can be centrally archived and published in alternative, accessible formats such as braille and digital text that can then be read back by assistive or "screen-reading" software. Guidelines like WCAG are primarily intended for HTML/XHTML+CSS web pages, but the W3C’s Web Accessibility Initiative also encompasses Rich Internet Applications.

NIMAS is good news, as it ensures students with visual disabilities have equal access to learning materials. But there are two key words here I want to point out: "content" and "alternative". The material (content) is in an additional (alternative) format to be used with assistive technology like the DAISY/NISO Digital Talking Book. And that’s a good thing, as it is all about the content, and the presentation should not hinder access to learning, as print publications and many older (and unfortunately, current) web sites do.

However, NIMAS implies that publishers and state and local agencies have to deal with the burden of managing multiple formats for the same publication, albeit a burden that must and should be carried considering the goal. One of the good things about the W3C’s accessibility guidelines is that it provides a means for all web content to be accessible, whilst at the same time have presentation that is clear and easy to follow for those who can see the screen i.e. one piece of content, multiple reading channels.

PDF is related to all this too. It’s already a common format for educators and publishers to use for learning materials (yes, eBooks are back!), as well as being the number 2 file format for documents on the internet today (after HTML). It’s also a document format required by NIMAS for submitting and storing images. But PDF is typically thought of – and used – as a presentation format for consistent viewing of content on screen and in print. It can, however, also be used a single source for content that can be richly formatted and be interactive with assistive technologies.

By default, PDF’s created using the PDFMaker that comes with Acrobat 5.0 and later include structure or tags that make it somewhat accessible, but not completely. In order to ensure PDF learning materials are completely accessible when opened with Acrobat or Reader, a document author or producer must use the tools available to them in the Professional version of Acrobat. Version 8 of Acrobat Professional includes a number of tools to not only verify that PDF documents are fully accessible and comply with W3C guidelines, but also has tools to add information to the document that allows authors, publishers and producers to ensure their documents work with assistive technology correctly, irrespective of how they were created. For example, adding alternative text to images and form objects, and defining a reading order for a highly stylized document that may have been created with Adobe InDesign, say.

But what should be included in a PDF to ensure a document is accessible to students? That brings us to yet another standard: PDF/UA or PDF, Universal Accessibility, which is currently a draft. The PDF/UA Committee, under the auspices of AIIM, is creating a set of guidelines to what should be included in a conforming PDF so that it is truly accessible by all. It’s a promising, important and large effort in ensuring the same PDF-based content students use to learn from can also be viewed by those who have special needs. I hope organizations like the AFB are paying close attention to this emerging standard, and consider it as part of their own guidelines and requirements, especially since their target audience is already used to working with – and has workflows around – the ubiquitous PDF format.

As mentioned on the AIIM web site and the committee’s wiki, PDF/UA is not a "how-to". If you’re looking for that kind of information, I suggest taking a look at the resources that Adobe provides on its accessibility pages. The information here was created for Acrobat and Reader 7.0, but is still relevant to those of you who are using Acrobat 8 and would like to learn more about this. It’s informative reading that I suggest anyone in education take, even if just to be enlightened about what should be done to make sure documents – any document – are accessible to our students and colleagues with special needs.

Welcome back!

It’s been a while since I’ve posted to this blog, but I’m glad I can get back in to the swing of things again.

For the last few months I’ve been all over North America showing educators all the new features in Acrobat 8 and brainstorming with them some of the ways that they can use them. Whether you’re a teacher or an administrator, a researcher or a student, I really do believe that this technology can help you save a little bit of time each day to focus on what you really should be – or want to be – doing. And there’s a lot in this release! Ted Padova (famed author of the Acrobat PDF Bible series of books) talks about his top features here on the web site.

So stay tuned; I promise to get this blog rolling again.

Thanks for reading!