There have been a number of recent discussions regarding the requirement for ALT text and the use of LONGDESC. Many of the suggestions and proposals appear to be based on supposition rather than actual feedback. The following email exchange from the WebAIM mailing list might give pause to consider:
The original question was: > How does blind > user access graphical information like flow charts, organisation > charts? What are the most common methods and tools used? Does it > allow a blind user to have the same experience as sighted users? > What does a blind user think of the accessibility of this kind of > graphics on the web? Do they have some ideas of what they would > like to see happen? When accessing a flowchart or organisation > chart, what kind of information are they interested in? To which one respondentwrote: > Good question! <snip> I believe you are talking about braille > in general. (I have friends who are blind who readers verses "blind" > use large print or CCTVS to access graphics.) > > Here's a bit of information to get you started. > > I work closely with four speech readers who require statewide data. > Two prefer getting hard data for charts or graphs using an excell > spread sheet and two want a description using word. > > For maps and building layouts we still have requests for tactile > maps. We are blessed with a tactile embosser (makes graphics in > tactitle format) and people that know how to use it. This is not > always the case. But such can be made by organizations like American > Printing House. > > Workflow layout, if made in something like Viseo, just needs to be > redone using alternative text. When org charts are made in an > electronic formate, even if accessible, we always get requests for > alternative descriptions. > As we continue to discuss the usage and necessity of attributes such as ALT and LONGDESC, I think that the above should be kept in mind - not every user will access visual materials the same way, even if they have similar needs. Sometimes cows need paths, other times they need to free-range... JF