Blind users deserve to be afforded a programmatically determinable way to obtain equal access to a long description of content images as well as decorative images whenever an image already has a link which is mapped to another function.
The majority of blind people lose their sight later in life, either progressively, or through an accident. They have understanding of vision and are able to "visualize" what things look like in their mind's eye. This is an important part of them. They appreciate descriptions. Some have described themselves by saying, "I am blind. I am a visual person. I just can’t see". Other people born blind may not be interested in what such an image looks like. If they don’t want to listen to the long description, they won’t. In either case they deserve the opportunity for an equal experience.
Being programmatically possible to separate the activation of the longdesc for exposure from the UA's universal link activation action (which is usually activated with the ENTER key, the SpaceBar, or by mouse click), so that a linked image retains the expected behavior in response to user interaction while a discrete mechanism is used to retrieve the long description provides accommodation for blind users.
This functionality is taken for granted by sighted users as they
automatically see what an image looks like while being able to
directly access a parent
<a> element mapped to a
Attempting to force dual functionality into single functionality is unworkable because it is impossible for one link to take a user to two locations.
<img>elements on the web that need long descriptions not to have a parent
<a>element mapped to a different task unrelated to a long description is unrealistic, i.e., a thumbnail <img> that links to a larger .jpg as evidenced by sites such as the National Institute of Dental and Craniofacial Research.
ARIA provides no mechanism for separating out what contributes to the accessible description and a navigational link.
Removing the possibility for direct, dual, programmatic access
to both a long description and a separate
a href on an
<img> element would be: