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Re: Adobe Acrobat PDF Tables issue

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From: Philip Kiff
Date: Oct 12, 2020 1:37PM

Yes, to start with, I would re-iterate what Lisa has said. Generally, if
you have a table that is properly tagged (in the Tag tree, not the Order
panel) using TR for each row and then TH for header cells and TD for
data cells, then you shouldn't need to tweak the order of the table.

In addition, I notice that you are using the "Order" panel (sometimes
called the "Z-Order" pane) to re-arrange the order of items in your
document. I would instead focus on re-arranging items in the "Tag" tree.
When you re-order items in the Order panel, behind the scenes, Adobe
Acrobat is actually making structural and sometimes destructive changes
to the "containers" in the Content pane. For some simple documents, this
is fine, and the re-ordering can be done without incident. But for
others, this behind-the-scenes restructuring results in a broken file.
In the case of some PDF files, it is literally impossible to fix the
reading order in the Order panel without breaking the visual display of
the file.

By contrast, when you adjust the order of the tags  in the Tag tree, it
does not affect the visual display of the file. And re-ordering the tags
in the Tag tree does not affect the order in the "Content" pane, so you
are less likely to end up with an accidentally broken file. The
accessibility "tags" in the Tag tree exist on a separate "layer" of the
PDF from the visual (Content) layer.

The Tag tree is used by most assistive technology to determine the order
of the content. The Order pane is used by technologies that are not
aware of accessibility "tags" - these are usually older and less popular
technologies. Unfortunately, the list of these non-tag-aware
technologies includes Adobe's own "Read Aloud" function built into
Acrobat as well as Read-Write Gold (still popular in many school
systems) and some braille displays.

Phil.

Philip Kiff
D4K Communications


On 2020-10-12 14:31, L Snider wrote:
> Hi Laurie,
>
> What are the tags doing? I have always had to remediate the tags, but very
> rarely the reading order after the tag remediation. Are the tags correct in
> terms of TD, TH and order there (and did you test it with the braille
> accessible text file to see what it looks like there?).
>
> Cheers
>
> Lisa
>
> On Mon, Oct 12, 2020 at 3:01 PM Laurie Kamrowski < <EMAIL REMOVED> > wrote:
>
>> Hi all,
>>
>> I am having a rough time with trying to touch up the reading order in my
>> PDF that I have created. It's too large to attach here but I can provide it
>> if requested (it's 2 MB). Also, I am adding a link to the youtube video
>> where I recorded the issue as it happens.
>>
>> I don't know what I'm doing wrong, or if my machine just doesn't have
>> enough RAM, but I'm just really frustrated. Any help would be very much
>> appreciated.
>>
>> This is the youtube video:
>> https://youtu.be/QLgTJ1yBx8k
>> Laurie Kamrowski
>> She/Her/Hers
>> Accessibility Specialist
>> Mid Michigan College
>> >> >> >> >>
> > > >