Transmission curves of the NAC (first panel) and WAC (second panel) filters. The third panel shows the transmission curves of the NAC focus plates, the anti-reflection coated plates, together with the total reflectivity of the NAC mirror system. The transmission curve of the WAC anti-reflection coated plate and the total reflectivity of the WAC mirror system is shown in the fourth panel. The last panel shows the quantum efficiency of the NAC CCD as measured on the flight model at room temperature (black solid line) and close to operational temperature (red dot-dashed line).