Dragan,
I'm not sure if I've ever played with doing it that way. But that does work very well.
update - but it won't give you scroll bars.. you'd have to do those on your own, but that isn't too hard to do.
>And if the image is inside a container, then its overall visible clip will be the container itself. Then it's just up to the programmer to manipulate image's .left, .top, .width and .height to achieve zoom in and out, scroll in any direction.