Designer does not reflect edits to bitmaps and so on
Image content (for example mypic.jpg) is cached at the process level and this means that editing an image or replacing an image on disk requires closing VS and re-starting it to see the changes to the image.
Changing the Source property on an Image in the Property Browser is not supported
Modify the Source property for images in XAML.
Resizing Image or Video Controls at Design Time Has Known Issues
When resizing an image or video control at design time, the position of the control may inadvertently change. There is also an issue with resizing through a size of 0,0.
The workaround is to use either the property browser or XAML Editor.
A '\' as a Path Separator is Not Supported
For example the following will not work in the designer:
<Image
Source="\images\img_7329.jpg"
Height="Auto" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Width="Auto"></Image>
However, changing the path separator to the following will work:
<Image
Source="/images/img_7329.jpg"
Height="Auto" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Width="Auto"></Image>