1. A method of using a camera-equipped mobile telecommunications device, comprising: capturing first imagery of an object, when the device is at a first position relative to the object; capturing second imagery of the object, when the device is at a second, different, position relative to the object; by reference to the first and second imagery, determining pose data that characterizes at least part of a geometrical pose between the device and the object; through use of said determined pose data, obtaining image data corresponding to the object with reduced perspective distortion, relative to at least one of the first or second captured imagery; and processing said obtained image data to derive identification data therefrom.