[thelist] Re: Accessibility and alt text - quality vs quantity

Clive R Sweeney clive at designshift.com
Wed Jan 28 01:16:14 CST 2004

>> Jono Young wrote:
>> Whenever I build a site, if there is an image that does not convey
>> message, or serve to inform the user, etc. I always just use
<alt="">.  For
>> instance, on a spacer gif I would use:
>> <img src="../images/whatever.gif" width="1" height="1" border="0"

> Trent Whaley wrote:
> Whenever I build a site, if there is an image that does not convey any

> message, I think "do I really need this image?".

I've been trying to put together an article on this issue, but since
it's come up here:

It's hard to find a resource that's convincingly definitive on how the
"alt" attribute is best used. I think it's obvious to most of us now
that an empty string is best for our spacer GIFs, although even better
is to get rid of the spacer GIFs. That seems to be an easy call.
However, there are many well-intentioned designers now who are adding
thoughtfully descriptive alt attributes for the more decorative images
on their sites, and I have to wonder if they're doing the right thing.

Trent says, "if there is an image that does not convey any message, I
think 'do I really need this image?'" While that's always a question
worth asking, I think there's a good argument to be made for using
images as "visual interest" to brighten up a page and make it more
interesting to look at. For sighted visitors to the page, such an image
serves a very real purpose and if properly optimized, should not be too
much of a drag on the page download time. I suppose it's the same as
pictures in a magazine. If we cut every print image "that does not
convey any message", our magazines would be thinner and much less
enjoyable to read.

I suppose one could look at it another way, and say that *every* image
conveys a message. Some of those messages, however, are only properly
conveyed by seeing the image. Like a joke, if you try to explain it, the
effect is lost. In the same way, some images work for our sighted
visitors, but trying to explain them to visitors who can't see them is a
waste of time and effort, because the effect of our decorative images is
purely visual and instantaneous.

Other images convey specific messages that can and should be expressed
to those who can't see them. Examples might include a graph that
illustrates and adds to the text or, possibly, a photo taken of a person
committing a crime that is being discussed in the text.

I haven't yet used a screen reader to help me understand the experience
of a blind person visiting a website, but I can try to imagine what that
person would or wouldn't want to hear from the page. If I were creating
a page about a local baseball team, the Durham Bulls, I might have a
photo of a player at bat. Sighted visitors to the page would see part of
the beautiful ball park, the great colors of the Bulls' uniform, the
athleticism of the captured motion, and more. I'm not going to attempt
to say all that in an "alt" attribute. On the other hand, if I just say,
"Player at bat" it's basically worthless and if I say, "Joe Morgan hits
one out of the park", I'm still not capturing the image in a way that
adds to a blind visitor's experience of the page. In such cases, I would
think any alt text at all is probably just annoying noise.

I'm still struggling to come up with a good alt text policy, but I'm
tending to think that most images on the Internet would work best with
empty alt attributes (that is, "empty" as in ""). But I could very well
be wrong, so I'm open to any informed opinions.

Clive Sweeney
Durham, North Carolina

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