Abstract: A mirror is scanned to provide an image of a portion of the Earth to a multiband focal plane array (MBFPA) of optical detectors (an “imager”). Initially, the mirror is positioned relative to a first axis. The mirror is then scanned about a second axis and repositioned relative to the first axis while scanning the mirror about the second axis. This invention may be used in a weather satellite to remove prevent/reduce errors in pixel-to-pixel registration within an image frame and errors in band-to-band that occur when the various imaging bands (e.g., visual and infrared) of the MBFPA are used to image or scan selected areas of the Earth. The present invention positions the mirror relative to the first axis (e.g., elevation), and while scanning the mirror about the second axis (e.g., azimuth), the mirror is regularly repositioned in a prescribed manner relative to the first axis.