It might even be worth removing this from the list of examples here (a more involved example is given in its own docstring).  Mostly `setOrigin` is something I needed to have for when people reset the origin (or center) of an image, in which case we also update the image's wcs.  

Maybe the fact that I couldn't come up with a simple example is indicative that it's not an operation that users would normally want to do directly.