Earlier this year we set out to make the PDF version of Ability more accessible. However, subscriber David Falcus sent us examples of how pages in the more accessible version failed to display well. Here is his letter and subsequent correspondence with our consultant Ted Page.
Issues with Ability’s accessible PDF
With regards to the accessible PDF I have done a quick test and unfortunately I did find issues.
I have enabled document reflow, set a high contrast colour scheme, and zoomed in to 150%.
I think this configuration is something that is quite valid, and something that I have tested with on PDF files in the past and found the accessible ones to work well with.
There are many pages in the document however that do not display well. I have included screenshots of a small selection of them below.
· Pages 7-15 are just displaying as black.
· Page 4 below has text that overlaps.
· Page 17 below has quite a lot of information missing.
· Page 26 has text over the image.
Accessibility Practice Lead, BT TSO
Reflow view of PDFs is a broken technology
I'm really sorry, but I'm afraid I would have to disagree with David Falcus's view that PDF's reflow view is a valid configuration.
I think the near universal view of people who work with PDFs is that reflow view is a more or less completely ‘broken’ technology.
A document may work in reflow view, but it is never guaranteed. The only control I or anyone else will have over reflow view is in the reading order. There is just no functionality for fixing overlapping text or making text reappear when it is missing or fixing any other problem.
Probably the leading expert in PDF accessibility in the US is Duff Johnson. He is the chairman of the PDF/UA committee and vice chairman of the PDF Association.
Duff recently wrote an article entitled ‘pdfGoHTML: PDF Reflow Done Right’ http://duff-johnson.com/2013/01/21/pdfgohtml-pdf-reflow-done-right/.
The article is not actually about the problems of PDF reflow view per se, more about a product to do what PDF reflow can't.
But I am aware that Duff's view is very much that reflow is currently unworkable. I have also had discussions with the subject of the interview, Olaf Drümmer, on the same topic. He gave up on reflow view years ago.
However, I think there is a solution which is to produce the magazine as an epub as well as a PDF. Once you have a well tagged PDF you can create an ePub relatively easily from it.
Is Adobe Acrobat’s reflow really broken?
Thanks very much for the comprehensive reply.
I have to admit that this area is something that is relatively new to me – so I am busy trying to get up to speed.
The comment “…near universal view of people who work with PDFs is that reflow view is a more or less completely broken technology” is interesting.
I have been searching the web and cannot really find anything to back this up – perhaps this is a view that the experts have – but are not really articulating to a wider audience? If the reflow view is so bad why is there not more public criticism of Adobe?
What led me to the original view was that I did find some documents on the Adobe site that worked 100% correctly in the reflow view – so certainly with some types of document at least that view is workable.
It is a bit of an ironic situation that we now have the PDF/UA standard, but potentially the most popular PDF viewer is not capable of taking full advantage of it.
Whilst pdfGoHTML is interesting, at the moment it is only available for the full version of Acrobat, which is not really a realistic option for the majority of users who would have the free Adobe Reader.
I need to do some more investigation on this and will let you know if I come to any different conclusions.