1. An image taking apparatus comprising a plurality of imaging means each including a lens with a variable focal distance and an image sensing device, the plurality of imaging means being disposed such that their viewpoints are substantially coincident with each other and image areas partially overlap each other so as to allow it obtain a wide angle image by connecting a plurality of images obtained by the respective imaging means, each imaging means including: a set of a plurality of mapping tables prepared for various respective values of the focal distance, each mapping table representing the correspondence for one of the various values of the focal distance between a particular coordinate system and a coordinate system in which an image taken by each image sensing device is represented; a controller adapted to select a mapping table corresponding to a focal distance used to take images by the image sensing devices; and a mapping unit adapted to map each image into the particular coordinate system in accordance with the correspondence described in the mapping table selected by the controller.