4.1 Overview

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ACS employs two fundamentally different types of detectors: CCDs for use from the near-UV to the near-IR, and a Multi-Anode Microchannel Array detector known as a MAMA for use in the ultraviolet. The CCD and the MAMA detectors are used in different ways and impose their own unique limitations on the feasibility of observations performed with them. This chapter covers the properties of the ACS detectors, descriptions of how to use them to optimize scientific programs, and steps needed to ensure the feasibility of observations.