Following my article on high resolution graphics for my blog, I have looked around for some plugin that would handle high DPI graphics for this blog. I have found WP retina 2×, which use Apple retina approach to the problem: have a second image at twice the resolution with the string "
This is particularly useful for the thumbnails, in this blog they are typically 250 pixels wide, when the thumbnail was generated from a higher resolution image, then the plugin can generate a 500 pixel wide thumbnail and substitute that on high DPI displays. Of course, this does not work for hand-optimised low palette count PNG files, which I often used.
I generated substitute images for some the thumbnails in this blog, but for many the available image just has to few pixels, or was added to the blog using an older media mechanism that the plugin does not recognise, but still, it works, and from what I saw the images do look better. Still I only do periodic checks so if you see issues, please let me know.