The Arundel Assumption And Revision Of Some Large-Scale Maps: Limiting Factors

Abstract

Although ortho-photographs are known to be superior to their rectified photograph counterparts, production and use of the latter may still be preferable in certain cases, especially in situations of flat terrain and in circumstances favoured by the Arundel
Assumption. The rather common practice of stating or using the Arundel Assumption without reference to appropriate mapping standards (except mention of its use for graphical plotting) is a major cause of inaccuracies in map revision. This paper describes an investigation to ascertain the applicability of the Assumption to the revision of the Ordnance Survey 1:2500 Overhaul map series. The maximum permissible camera tilts tolerable for two mapping accuracy standards of the series are considered as well as the implications for the Air-Graphic/Air-Ground revision methodology

Keywords: Ortho-photograph,ArundelAssumption, camera tilt, rectification, large-scale maps, map revision.

Journal of the Ghana Institution of Engineers Vol. 5 (1&2) 2007: pp. 7-12