The reason your small image and zoom image are the same is because your small image and product image size are set exactly the same.Originally Posted by digidiva-kathy
You can change this by going to Admin -> Configuration -> Images and change the setting of Product Info - Image Width and Product Info - Image Height to something else.
You do not have to change this setting if you really want you product image to be 120 X 120 just keep in mind that the zoom is using the product image as the display of the enlarged image.
Hope this makes sense.
Bookmarks