The two MOS-CCD cameras are used to detect low-energy X-rays. Each camera is composed of seven silicon chips (one in the centre and six circling it), with each chip containing a matrix of 600 × 600 pixels, giving the camera a total resolution of about 2.5 megapixels. As discussed above, each camera has a large adjacent radiator which cools the instrument to an operating temperature of . They were developed and built by the University of Leicester Space Research Centre and EEV Ltd.
