>(thus making the page load slower) The difference is tiny. If your images are on the same domain as the html, you'll have no extra overhead from the ssl hands

>(thus making the page load slower) The difference is tiny. If your images are on the same domain as the html, you'll have no extra overhead from the ssl handshake (thanks to http keepalive), and the symmetric encryption used in an existing ssl connection will have a negligible impact on performance. I can think of two reasons you want https, even for just images: 1) Even though modifying an image in flight will probably not have major security implications, you can't be sure. Perhaps a carefully edited and resized image could alter the layout of a form, tricking the careless user into publishing information they didn't mean to. 2) Perhaps your adversary is just a teenager bothering people trying to be productive at a coffee shop. Including a 10000x10000 image that makes the page unusable, or replacing your logo with porn isn't exactly something you want, even if it doesn't compromise anybody's bank account.