"Thanks +Joseph Siroker , I'm a big fan of Mr Margulis' (the Canyon Conundrum changed the way I think about colour!) - these were uploaded from telephone straight to Google+ without post processing. My plan is to take some 'proper' photos from similar locations at some point - just hope the clouds are as dramatic! Will give the actions a go on this though ;)"
"+Bryan Sinclair no idea - I went to my local printer who deal with oversize display printing and asked them to add the file onto a larger print run they had. Most commercial printers should be able to give you a decent deal. Really don't know about home printing this kind of thing - would be curious to know if it's possible / what's required."