steve: added start of section on How long should a short text alternative be?

steve: added start of section on How long should a short text
alternative be?

http://dev.w3.org/cvsweb/html5/alt-techniques/Overview.html?r1=1.10&r2=1.11&f=h

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RCS file: /sources/public/html5/alt-techniques/Overview.html,v
retrieving revision 1.10
retrieving revision 1.11
diff -u -d -r1.10 -r1.11
--- Overview.html 13 Apr 2010 10:29:24 -0000 1.10
+++ Overview.html 13 Apr 2010 15:10:20 -0000 1.11
@@ -329,7 +329,8 @@
   <li>If the alt attribute content is too long it may cause raeding issues in some assistive technologies.</li>
   <li>Semantic structure cannot be added to alt attribute content.</li>
 </ul>
-<p>&nbsp;</p>
+<h6>How long should a short text alternative be?</h6>
+<p>The answer to this question very much depends on the context an image is being used in. While there are no definitive right or wrong lengths for text alternatives provided using the <code>img</code> elements <code>alt</code> attribute, the general consensus is that if the text alternative is longer than  75-100 characters (1 to 2 sentences), it should not be considered a short text alternative and should not be presented using the <code>alt </code>attribute.</p>
 <h3>The <code>figure</code> and <code>figcaption</code> elements</h3>
 <p><span class="note">to do</span></p>
 <h5>Advantages:</h5>

Received on Tuesday, 13 April 2010 15:11:20 UTC