Link to image popup?

I initially didn’t think that this would work, but I have just tried a test which indicates that this can be achieved with Alligator Popup. You would use the shortcode as normal, but specify the path to the image instead of a page and include the height and width of the image.
eg:

[popup url="http://sitename/wp-content/uploads/image.jpg" height=900 width=700]link text[/popup]

You can also wrap the shortcode around an image instead of the link texteg:

[popup url="http://sitename/wp-content/uploads/image.jpg" height=900 width=700]<img src="http://sitename/wp-content/uploads/image-150x150.jpg" alt="myimage" width="150" height="150" />[/popup]