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Re: Alternate text for images having caption adjacent


From: Whitney Quesenbery
Date: May 30, 2014 2:24PM

I'm sorry Jared, but I don't understand the distinction you are making.

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

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

The alt text needs to be written taking into account the other information
on the page.

* Is there a caption, and what does it say?
* Is the information in the image repeated or explained in the text?
* Is the image of value on its own?

A few more examples:

The text describes a process flow, and is accompanied by a diagram with the
same information. I might write alt text that says "Diagram of the process"
so all readers know what this image is, but not repeating any more

Last, I NEVER use null alt text for images that are substantive
illustrations. I have had too many occasions when someone wanted to know
that it was available, or to be able to identify which one it is to send it
to someone.

The biggest exception in my mind are thumbnails that are really elaborated
visual bullets in a list or menu or ...

But one of the big gaps in many CMS is that their automated generators
don't let you indicate null alt, so you have to manually edit code or
markup, because they can't tell the difference between "blank" and "null".
All of this just the sort of boring problem of programs that don't consider
the authoring user interface and create tools that support, instead of
actively making it hard, to make content accessible.

On Fri, May 30, 2014 at 12:40 PM, Jared Smith < <EMAIL REMOVED> > wrote:

> On Fri, May 30, 2014 at 10:15 AM, <EMAIL REMOVED> wrote:
> > How about we provide alt ="" and add an off screen message "image" along
> with description?
> There is no accessibility requirement that you provide a description
> of what the image looks like and there's no requirement that users
> know that an image is present. All that is required is that you
> provide alternative content for the image. In short, image
> descriptions (what the image looks like) are usually not the same as
> alternative text (the content the image conveys).
> Alternative text is required for accessibility and goes in the alt
> attribute or in adjacent text. Image descriptions or identifications
> are NOT required for accessibility and should usually NOT go in the
> alt attribute (unless the description and alternative text happen to
> be the same). If you choose to add verbose descriptions of the image
> appearance (as Bevi described regarding NatGeo Magazine examples),
> they should probably be made available to everyone in a caption.
> When we train about alternative text, we never use the word
> "description" - instead we use "content" and "function". When you
> focus on providing the image content and function in alternative text
> (whether via the alt attribute or adjacent text), then the results are
> usually better, more succinct equivalents.
> Jared
> > > >