The responsive quantum efficiency (RQE) of the WFC and HRC CCDs is shown in Figure 4.1; it includes corrections needed to reproduce the instrument sensitivity measured on orbit (ACS ISR 2004-08
). The total spectral response of the camera (see Figure 5.7) is given by the convolution of the RQEs shown here and the throughput of optical elements of the camera. For example, the WFC silver coated mirrors, while enhancing the reflectivity in the near-IR, impose a violet cutoff below 370 nm.
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