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Re: Longdesc implementations/alternatives?

for

From: Jared Smith
Date: Jun 24, 2015 9:41AM

I think the best approach to complex images is to either place the
long description in context (perhaps a data table immediately after
the image) or to provide a link to a long description page.

While there is minimal support for longdesc, it is still almost
entirely screen reader specific. Long description pages can be helpful
to all users, so efforts should be taken to make them easily presented
to all users. A link is the best way to do this.

The primary issue with using aria-describedby is that any structure in
the referenced element is lost - it is read as a stream of text. On
your example page, all of the headings, lists, etc. are lost when read
in conjunction with the image. This also means that the screen reader
user can't navigate or control reading within the description. They
can't pause and start reading where they left off, for example. And
because long descriptions are, by definition, long, this can pose
significant issues. Also, if the referenced element is hidden, it may
not be read at all -
http://www.paciellogroup.com/blog/2015/05/short-note-on-aria-labelledby-and-aria-describedby/

Personally, I've never used or recommended longdesc. It does not
provide any benefit over a standard link to the long description page.

Jared

PS - This is where John Foliot responds to defend longdesc. I know
this because we've had this conversation already at least 20 times on
this list. :-)