I have recently created an attachment.php template for my site which is working fine.
However I would like to use one template for images attached to a page, and a different template for images attached to a post.
For example here is an image attached to a page: http://www.cathedralcityguide.co.uk/the-cities/bristol/bristol-harbour/
and here is an image attached to a post: http://www.cathedralcityguide.co.uk/2013/01/happy-new-year-from-cathedral-city-guide/fireworks-small/
Looking at the template hierarchy I can't work out to do this. Is it possible? Any help much appreciated!