title: wpf datatrigger on an image source
body: <p>Assuming the binding is right and the image files are where they shuld be, can anyone spot why the image in the xaml below won't change when the trigger evaluates to true?</p>
  
  <p>Cheers,<br>
  Berryl</p>
  
  <pre><code>&lt;Image Source="..\..\Images\OK.png" Grid.Column="2" Stretch="None"&gt;
      &lt;Image.Style&gt;
          &lt;Style&gt;
              &lt;Style.Triggers&gt;
                  &lt;DataTrigger Binding="{Binding TimeSheet, Converter={StaticResource overQuotaConv}}" Value="True"&gt;
                      &lt;Setter Property="Image.Source" Value="..\..\Images\Error.png"/&gt;
                  &lt;/DataTrigger&gt;
              &lt;/Style.Triggers&gt;
          &lt;/Style&gt;
      &lt;/Image.Style&gt;
  &lt;/Image&gt;
  </code></pre>