You should be able to scroll the image in full-screen, even if the whole image isn’t shown at once, is this the case?
The image is scrollable, but only downwards (i.e. there’s no way to scroll to see the top of the image, only the bottom).
We’ve been playing around with having two modes, “a fit to height / width” and a “zoomed in / original” size mode. You will be able to cycle between them by clicking the image.
I like this idea!