1. An image display system comprising: an image display apparatus for displaying a derived image of an object, the image display apparatus being positioned adjacent to the object and being moveable with respect to the object, and an image processing unit for processing previously-recorded image information of the object into the derived image, wherein the derived image corresponds to an instantaneous position and/or orientation of the image display apparatus relative to the object but is independent of the instantaneous position and orientation of a head of a user viewing the image display apparatus, whereby the user can move to view the adjacent object without the derived image displayed on the image display apparatus being changed.