I have installed and am testing this plugin and while it is serving the correct images to retina and non-retina screens somehow the retina screens are not recognising that the retina-ready image they are being sent is already retina-ready so they are doubling its size (again) resulting in an image twice the necessary size. The example can be seen at the URL http://partito.draftsite.net.au. The top 'PARTITO' banner logo will have the URL of
http://partito.draftsite.net.au/wp-content/uploads/2013/03/partito_logo3.gif if viewed on a non-retina screen and has dimensions of 550 x 135 pixels. When viewed on a retina screen the URL being correctly served is
http://firstname.lastname@example.org however this image having dimensions of 1100 x 270 pixels is being displayed at twice its size i.e. the retina screen is not recognising that this is already a retina-ready image! What to do?