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Re: Longdesc vs d


From: Michael D. Roush
Date: Oct 28, 2003 9:03AM

First of all, let me offer my congratulations to your agency for taking the
step of proactively seeking to make your pages accessible! You are right
about the quality of the exchange of information on this list. I forgot how
much I missed it while I was away from it.

Now, about 'd-link' vs. 'longdesc'. As the story has been told to me (and
some research seems to verify), 'd-link' was designed as an intetrim
solution, between the time 'longdesc' was put up as a recommendation and
browser support for it becomes widespread. It seems to have come from the
good folks at WGBH/NCAM. And, as I said, it was designed to be a temporary
solution, until 'longdesc' comes of age.

I found this in Checkpoint 1.1 of the WCAG:
"For complex content (e.g., a chart) where the "alt" text does not provide a
complete text equivalent, provide an additional description using, for
example, "longdesc" with IMG or FRAME, a link inside an OBJECT element, or a
description link [this is a reference to the d-link system]."

Now, you mentioned trying to comply with Section 508, not specifically
mentioning the WAI. Section 508 specifically mentions using 'longdesc' but
not the 'd-link' technique. But, an argument could be made that a 'd-link'
keeps the spirit of the standard, and the list of examples given wasn't
meant to be exhaustive, or even that a 'd-link' qualifies as 'element
content' which is specifically mentioned. So, I'm not sure that the 'use
neither, because they aren't standard' suggestion holds. There is a bit of
double edged sword to using one or both, though. Using one will likely
leave those who routinely use the other a bit confused or left out. But
using both may make both groups confused! Since you have so many pages, and
the 'd-link' was suggested as an interim solution (if you take it as a valid
suggestion to begin with! Some don't.), I would not decide to add any more
d-links than you currently have, and work towards going to using 'longdesc'.
Otherwise, you are going to have a bunch of d-links you added recently to
get rid of once 'longdesc' support is better - and it will get better sooner
if more people use them. Only very complex images requiring longer
descriptions would be good candidates for the 'longdesc' (and likewise, a
'd-link'), so there may not be a large number of them even on such a large
website. The bigger issue over 'consistency' is probably alerting users
what the little 'd' means, since the practice is not in great wiidespread
use, most people still have no idea what it is.

My suggestion would be to develop an accessibility policy and then stick
with it. You have a lot of archive pages to deal with. Ten thousand pages,
updated at 40 per week, would take you 5 years to accomplish. By then, I
imagine lots of things will change. So, perhaps something like:
"The Indiana Department of Environmental Management is committed to
providing accessible content to our users. New pages are designed to adhere
to US Federal Rehabilitation Act Section 508 standards for accessibility.
Older pages are in the process of being updated to comply with these
standards...(insert your criteria for updating pages and which pages you
won't update here)."

Then you have something to guide you as you look through those old pages.


----- Original Message -----
Sent: Tuesday, October 28, 2003 9:20 AM
Subject: Longdesc vs d

Our question is how long, if at all, should we plan to use the "d" for
complex graphics, since newer screen readers do support the "longdesc" tag?

Should we be concerned about consistency... offering the d on some pages but
not on others?

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