Wide field imaging

Abstract

New types of prime focus field correctors for Ritchey-Chretien telescopes which have significantly better imaging than those presently in use are discussed. A corrector consisting of two contiguous positive lenses of relatively low power followed by separated negative and positive lenses has been applied to the f/2.7 focus of the Cerro Tololo 4-m telescope. Also considered is a 2.0-deg corrector for the Anglo-Australian 2.9-m telescope.