Electrographic Detectors versus Charge-Coupled Devices: A Comparison of Two Quality Panoramic Detectors for Stellar Photometry

This chapter evaluates the relative merits and practicality of two integrating photon-detector systems for the specific problem of accurate wideband photometry of large numbers of faint stars: A Griboval electrographic camera (GC) used on the f/l0 1-m aperture Yale telescope at Cerro Tololo and a thinned, rear-side-illuminated RCA charge-coupled device (CCD) mounted at the f/2.6 prime focus of the CTIO 4-m telescope. A field in the outskirts of the globular star cluster ω Centauri that included faint photoelectric and photographically “smoothed” sequences was chosen as a test object and was observed in the B and V pass bands with both instruments. The two sets of images were then subjected to a variety of tests and comparisons to characterize their photometric properties. Relative detective quantum efficiency (DQE) was determined from internal errors of star magnitude measurements on different exposures and also from background noise statistics.