Panoramic image automatically cropped when animated

I have a very wide panorama picture that I have sized up so the height of the picture is the height of the slide and the left edge of the picture is aligned with the left border of the slide. When I try to use any animation that moves it horizontally (fly in, move along path, fly out to the left) it's beeing cut off at twice the width of the slide (see attached image). In other words only like 1/3 of the image is seen moving then it's cut off but goes on to move. It doesn't help to change the speed or duration or length of path - it's the same anyway. Why? Has powerpoint some invisible border outside the slide where it cuts off images bigger than twice the size of the slide? How can I pan through the whole panoramic image without it being automatically cropped?