Hi Ed. The tool looks good but unfortunately I don't have sufficient images of my own to try it out properly. I have 2 Pluto images but one is really under exposed (#newbieproblems) so there's nothing to compare to. As Caio suggested it would be good if you could access all images in the gallery.
One thing to note was I was running Internet Explorer 10 initially and the when the images were loading they'd just sit at 0% so possibly an issue with older browsers. I upgraded to IE11 and it worked a treat though.
I appreciate you sharing, I'll certainly use it when I get more photos to try out, I think it could be really popular