OBSOLETE!  DECam does not have an ADC
Prime Focus Atmospheric Dispersion Compensator

Empirical and theoretical modeling of the PFADC Corrector on the Blanco 4m Telescope

T. E. Ingerson
(1997)

Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatories
Cerro Tololo Interamerican Observatory, Casilla 603, La Serena, Chile

The National Optical Astronomy Observatories are operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation.

Abstract:
A new set of corrector optics incorporating atmospheric dispersion compensation is now in routine use at the prime focus of the 4m Victor M. Blanco telescope at CTIO. This corrector is described and direct photographic measurements of the optical field angle distortion (OFAD) coefficients are compared with the values predicted from the optical design. The results are used to quantify the baseline behavior of this corrector and then extended to provide predictions of the telescope's performance with the new optics under conditions which have not been directly measured.