This page allows comparison of several images (usually the same object, but from different imaging/rendering sources) both side by side and by toggling between them. The left drop-menu sets the image for the left pane, and the right drop-menus set the images for the right pane. When you float your mouse over the image in the right pane it "toggles" between your two selections.
This page requires Javascript to be activated. All images are pre-loaded, so once they're loaded toggling performance should depend on the speed only of your computer and not of your connection. Be sure to turn your cache settings to "once per session" or "once per page" to prevent your browser from loading the images from the network.