RE: User Testing of Accessiblity Features

Hello,

We (the NYS Forum IT Accessibility Committee) did some work last year 
that indicated that screen reader users fell into two camps with 
regard to the usefulness of alt attributes for images.  Some users 
wanted to know what EVERY image was so that they could be sure they 
weren't missing information.  Others wanted only meaningful images 
described.  We proposed an additional attribute (two values only) for 
the img element to indicate whether the image was informational or 
just eye candy.

Using this flag, if supported by AT manufacturers, a user could 
select whether they wanted everything or just the informational text.

Andrew, I think there's some doubt in the W3C workgroups about the 
necessity for a number of attributes that have traditionally been 
used to provide contextual information to AT users, such as 
headers/id in tables, longdesc in img, and there is some question 
about the extent to which the alt attribute should be used.

Debi Orton

At 10:57 AM 8/28/2007, Andrew Kirkpatrick wrote:

>The main issue that I see related to the need for the alt attribute on
>images that have null alt is assistive technology support.  Screen
>readers like JAWS make attempts to read _something_ for images when
>there is no alt.  This is very important for linked images, but of
>questionable value for images that are not.
>
>Naturally, the extent of the value of the image varies on the type of
>the image, from spacer images (unimportant) to images bearing important
>content or text (critical), but if there is no alt attribute value then
>there isn't going to be information to read whether there is a null alt
>or not.
>
>The value of requiring alt on images has been that it is easy to tell if
>a person is totally unaware of certain accessibility issues by the
>absence of alt attributes on images that need them.  I don't think that
>requiring the alt attribute on all images should be sacred - equivalents
>for meaning images and linked images (including inputs with type=image)
>are required for accessibility, but I don't think it matters for other
>images whether the empty alt is there or not, so long as assistive
>technology ignores the image as they would with alt="".
>
>This seems like a pure technology question - I'm not sure what needs
>user testing here?
>
>AWK
>
> > -----Original Message-----
> > From: w3c-wai-ig-request@w3.org
> > [mailto:w3c-wai-ig-request@w3.org] On Behalf Of Lachlan Hunt
> > Sent: Monday, August 27, 2007 10:15 PM
> > To: joshue.oconnor@cfit.ie
> > Cc: HTML WG; 'WAI Interest Group list'; www-archive
> > Subject: Re: User Testing of Accessiblity Features
> >
> >
> > Joshue O Connor wrote:
> > >  Hi Lachlan,
> > >
> > > On the IRC I see that you say:
> > >
> > >> # [14:25] <Lachy> I did ask Joshue O Connor in that email
> > if he could
> > >> help out, since he offered his services for such things, but never
> > >> heard back about it
> > >
> > > The user testing is taking place tomorrow. Testing of Header/id
> > > combinations, @summary and @longdesc. I think I mentioned
> > that previously.
> >
> > I was aware that you would be testing those features, but I
> > think I was specifically referring to this email [1], where I
> > wanted to do testing of alt="" vs. no alt, etc.  Will that
> > issue be tested too, or left till another time?
> >
> > http://lists.w3.org/Archives/Public/public-html/2007Aug/0577.html
> >
> > --
> > Lachlan Hunt
> > http://lachy.id.au/
> >
> >

Debi Orton/oradnio@wsg.net
www.consideration.org
www.flashquake.org

Received on Tuesday, 28 August 2007 15:41:46 UTC