you also need to have the zoom set at around 50mm otherwise the edges wont match up correctly. Those were taken at around 28mm (wideangle) to get as much in as possible so they look curved. 50mm makes the angle look flatter and so is more suited to panoramic! it would be easy enough to join those using photoshop but it would require work, nothing a panoramic program could do as they simply blend them, not alter the angle of the ground etc or remove objects that have been cut in half etc.