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Re: Z-Order and Tag Order Need to Match?

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From: Ilana Gordon
Date: May 28, 2020 7:16AM

Hi All,

I knew when I asked about this subject there would be a flurry of
information. Thank you for your insight. Most of what has been said is not
new, i.e., that creating accessible PDFs is subject to the limitations of
software and the way documents are created. That's why it's important for a
group like this to exist. To make matters worse, the people who are
considering the efficacy of accessible documents are using a list of
criteria that are about as much as they know regarding making documents
accessible and not considering the usability outside of a checklist.

Consistently I find myself arguing with government staff who don't even
know what 508 Compliance is. There are arbitrary additions to Agency
checklists made by staff that are 508 police officers who know absolutely
nothing about it other than a document needs to fulfill a checklist. This
is probably true among many software developers as well.

As a remediator I find myself not only remediting 508 compliant documents
but constantly having to educate the very people who are making
uninformative decisions.

Thanks,
Ilana



On Thu, May 28, 2020 at 8:56 AM Duff Johnson < <EMAIL REMOVED> > wrote:

> Hi Lisa,
>
> There are no "multiple layers" in the PDF in this sense of the term. There
> is simply... content and tags.
> Content is text, graphics, form fields, annotations, etc.
> Tags are semantic structures (H2, P, Table, etc). These are applied to
> content and are used to describe "info and relationships' as per WCAG SC
> 1.3.1. Tags are the only means of providing these structures in PDF.
> Otherwise I fully agree with you, and am very encouraged to hear that you
> are working to convince other software developers to improve their support
> for Tagged PDF.
>
> Duff.
>
> > On May 28, 2020, at 07:53, L Snider < <EMAIL REMOVED> > wrote:
> >
> > Hi Duff,
> >
> > Unfortunately I know all about these layers, but there is still no
> reason.
> > There is no reason to have multiple layers, what you see should be what
> you
> > get...whether you print, tag or whatever...This is partially why, in my
> > personal opinion, PDFs are still inaccessible. 90% of the ones I have
> seen
> > since 2000 are a problem in some way, and most in major ways. Plus tags
> are
> > just one aspect of PDFs, people will all sorts of disabilities use PDFs
> as
> > you know well.
> >
> > I gave up on Adobe, they moved forward for a long, long time and the last
> > 10 years they moved backward. Not in InDesign, InDesign is amazing and
> > kudos to whoever worked on the accessibility aspect of it, now if they
> > could move back those people to PDF we might get back to where PDF
> > was...Microsoft has been kicking butt in terms of accessibility the last
> 5
> > years, so maybe one day Adobe will follow suit.
> >
> > I am now trying to find other PDF creation programs and convince them to
> do
> > better, may have a shot!
> >
> > Cheers
> >
> > Lisa
> >
> > On Wed, May 27, 2020 at 7:48 PM Duff Johnson < <EMAIL REMOVED> >
> wrote:
> >
> >> Hi Lisa,
> >>
> >> Content order and logical reading order are "separate" in PDF because
> the
> >> technology is obliged to represent content for different purposes.
> >> Rendering (e.g., printing) is a different purpose than accessibility,
> for
> >> example, and often requires ordering of content for processing purposes
> >> that differs from logical reading order. PDF was originally designed for
> >> maximum fidelity in print. Accessibility considerations were only
> addressed
> >> in 2000 with the addition of the Tagged PDF feature to the format.
> >>
> >> In 2020 the difficulty is not in the format but in the software.
> >> Unfortunately it remains the case that...
> >> PDF viewer developers don't do a great job of supporting tagged PDF in
> >> many cases. This is simply a business decision.
> >> Users continue to use software that doesn't understand tagged PDF
> instead
> >> of seeking out and demanding better.
> >> Authors continue to author content without consideration for semantics
> >> (e.g., use tab stops instead of table structures, etc.)
> >> I'll beat my usual drum once again: if you want better PDF support,
> >> complain to those who make your software. Demand better support for
> Tagged
> >> PDF. In 2020 there's simply no excuse.
> >>
> >> Duff.
> >>
> >>> On May 27, 2020, at 18:30, Paul Rayius < <EMAIL REMOVED> > wrote:
> >>>
> >>> As per ISO 32000, one of the intents of PDF is that the "accessible
> >> layer" and the visual layer are independent of each other.
> >>>
> >>> Paul Rayius
> >>> Director of Training
> >>> CommonLook
> >>>
> >>>