when to use longdesc for images (was RE: Short and long descriptions for links)

From: John Colby [mailto:John.Colby@uce.ac.uk]
> I'm trying to rationalise which type of images (with the
> exception of graphs and visual data presentation) that need
> a longdesc without sighted readers also needing that description
> available. Graphs and data images (my term), being the visual
> interpretation of some data - do they need to be described or
> does the data need to be stated? I can think of instances where
> either one or both would be suitable.

This probably depends heavily on the context, the purpose of the
site, and the purpose of the images themselves. Two examples:

- a web hosting site, with your generic "businessman with laptop" or
"handshake" images, probably do not need longdesc...it's not the fact
that it's the businessman with the laptop that's important here, it's
just generic visual fluff (although yes, some could argue that there is
a certain "emotional response" or similar triggered by the image, and
one could try to convey that in non-visual ways somehow...but usually
I'd suggest adding that in the normal copy as well - if, for instance,
you're using the image to portray the company as "dynamic and mobile",
this should feature in the body of the text as well...making it
unnecessary to add this non-visual information any additional way)

- an online art photography site, where you have a gallery of famous
photos; here, the images themselves will probably need to be 
"longdescribed": they're not just decoration, they *are* content, and it
is important that visitors "get" this content

Hope this made some kind of sense. Of course, there will be borderline
cases and blatant exceptions...it's mostly a judgement call that you need
to make, based on what purpose your images serve within the overall
purpose of your site.

Patrick
________________________________
Patrick H. Lauke
Webmaster / University of Salford
http://www.salford.ac.uk

Received on Tuesday, 21 December 2004 11:48:32 UTC