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Re: Alternate text for images having caption adjacent


From: Whitney Quesenbery
Date: May 28, 2014 7:44AM

I'd like to push the discussion of captions v. alt text a little further.

I work on a UX magazine, where we try to take accessibility seriously and
regularly publish articles on the topic. Many of our articles include
illustrations that are screenshots or images of other design artifacts. All
of our illustrations have captions, and a direct reference in the text.

The work of making the captions and alt text work together is one of our
ongoing discussions. I'd love any input, beyond the usual rules for alt
text, as I'm working on a style guide for our authors and editors.

1. If the *content* of the screenshot is not very important, do not
transcribe the text. The alt text briefly adds any descriptive details that
help someone visualize the image and make sense of the example.

If the *content* is important, use the alt text to identify the content
(say, repeat the title of the form or content being illustrated). Include a
box at the end of the article with the full text. (And even here,
transcribe only the part of the screen that is important to illustrating
the point.) Add a link in the caption (where it's possible technically)
that points to the long description in the box.

2. If the screenshot is compared to another, and well described in caption
or text, the alt text says whether it's the "before" or "after" (or
good/bad) image, in case a reader wants to know which is which.

If the comparison is sensory, echo words from the article to characterize
the visual impact. (For example: "Screen showing bland clip art" and
"Screen showing vibrant images")

3. Avoid de-minimus descriptions like "photo" in favor of what it's a photo
of. We use a word to describe the image only if the visual style matters.
(For example "Hand-drawn sketch" or "Visual mock-up" or "Screenshot".)

4. Think about how the alt text and caption read together, trying to make
them work as a coherent information unit

Don't hide any generally meaningful information in the alt text. Put that
in the caption, even if it makes a slightly longer caption.

Our alt text is sometimes longer than usual suggestions when the extra
words are helpful in understanding the design


On Tue, May 27, 2014 at 3:33 PM, Jared Smith < <EMAIL REMOVED> > wrote:

> On Tue, May 27, 2014 at 1:09 PM, Jonathan Avila wrote:
> > Alt text may often be different from a caption.
> Indeed. And in this case, the image would need an alt attribute value
> in addition to the caption.
> > For example, a caption might be "Washington crossing the Delaware", but
> the
> > alt text for the picture would in most situations need to describe more
> > than that to be a replacement of the image for someone who could not see
> > it.
> Yep, but if the full alternative *is* in context, adding
> alt="Painting. The description is in the text below." is silly and
> doesn't resemble alternative text at all, but it is what the WCAG
> definition and techniques suggest is necessary for conformance.
> Jared
> > > >