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Re: Writing good ALT descriptions


From: Korpela Jukka
Date: Jul 21, 2009 10:10PM

John E. Brandt wrote:

> Thanks everyone for your choices/suggestions. As I suspected might happen,
> there were choices ranging from the brief to the expansive. I will
> probably chose one that is somewhere in between.

In a complex matter like the alt attribute issue, if you ask for a brief
and understandable presentation, you are asking for two presentations. If
you also want something essentially correct, you typically need a third
one, too.

The problem here is really that you did not specify what you would use it
for. Probably as guidelines for web authors, but would they be novices or
highly experienced? The latter might be a tough case, since they think
they already know things and they probably have misconceptions and bad
practices they regard as expert methods.

It also matters how complex the pages will be and how images will be used
on them, as well as their overall accessibility. But considering typical
situations, an author will be usually far ahead of the vast majority in
alt text usage for accessibility, if he follows these rules:

1. Think how your page should behave when an image on it is not displayed.
2. If this behavior can be caused by specifying a short text alternative
(possibly empty) to the image, use that text as alt="..." attribute value
for the image.
3. Otherwise redesign the use of the image or its placement or content
around it and go to step 1.