Typically we save all of our images out 2x for mobile screens when doing images on non responsive designs.

We just coded a new batch of responsive templates. The images go from 600px wide for desktop views down to 320px wide for portrait mobile views. My first instinct was to save all the images out 2x the smallest size (320px). Doing this however means that if you are anything but 320px on a mobile screen you will still not have a crystal clear image.

My question is ... How do you account for those on larger mobile devices or phablets? Or landscape views? Is it still necessary to save the images out at 2x the largest width (in this case 1200px)? Im just asking to prevent this from being a bloated email.