Your edit picked up on exactly what I was going to reply with letting you know until I saw you already got there. Expanding on it, you can 'copy image location'

Your edit picked up on exactly what I was going to reply with letting you know until I saw you already got there. Expanding on it, you can 'copy image location' (at least in FF) to get the original image URL, and you can also middle-click 'view image' to open the image itself in a new tab. Both are useful tricks when rifling through images.