Publicize(Jetpack) Facebook Image selection

Hello,
I know that Publicize uses an image in a post for Facebook publishing but I would just like to have a standard image and not have to put it into every single post. Is there anyway to hard code an image location for it to use for my site posts ?
Currently it’s using the logo on the Header of my page which is a bit annoying as it’s a png with a transparent background so on the grey/white background of Facebook it looks odd.
Thanks for your help.