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Re: Alternate text for images having caption adjacent

for

From: Jared Smith
Date: May 30, 2014 3:23PM

On Fri, May 30, 2014 at 2:24 PM, Whitney Quesenbery wrote:

> I ask the question more journalistically: what information is this image
> adding to the page, or why has it been placed here.

These are certainly good questions to ask to determine the content of
the image, and thus the alternative text for that image.

> That information might be:
>
> * Text embedded in the image
> * Sensory
> * An illustration of a point made in the text
> * Detail not easily described in words
> * An example of something being discussed

If that information is determined to be useful content, then yes, it
should be conveyed.

> Last, I NEVER use null alt text for images that are substantive
> illustrations.

Likewise. It is of note that these types of highly illustrative,
journalistic images constitute a small percentage of images on the
web.

Our surveys - http://webaim.org/projects/screenreadersurvey5/ -
provide a good example of a brief alternative used on the complex
charts with the full text alternative in context. If one were to focus
on a *description* of one of the charts, it might be alt="A circular
pie chart with slices that are varying colors of red" - hardly an
equivalent, right?

As another example, imagine a photo of a woman wearing a headset in
the sidebar of a homepage. The image is linked to the customer service
area of the site. If you focus on providing a description of the
image, you'd probably use alt="smiling blonde woman wearing a headset
while sitting at a computer". Instead, alt="Customer Service" or
similar would be better and most efficient. A *description* of what
the image looks like or that it contains a smiling blonde woman is, in
this case, not relevant to the much-more-important *content* and
*function* of the image - that clicking it takes you to the customer
support page.

In our evaluation work we see thousands of images with alternative
text that simply describes what the thing looks like with little
regard to the actual content being conveyed. All I'm suggesting is
that we should rethink how we describe and present what alternative
text is so that the focus is placed on content, not visual
descriptions.

Jared