A luminaire comprising: a light source configured to emit a light beam; a mirror configured to controllably deflect the light beam emitted from the light source; a first motion assembly comprising: a motor (208, 228) mechanically coupled to the mirror and configured to rotate the mirror about a mirror axis of rotation (201, 221), where a change in a rotational position of a shaft of the motor relative to a body of the motor causes an equal change in a rotational position of the mirror; characterized by further comprising: a magnet (206, 226) mounted directly to a shaft of the motor, a center of the magnet being aligned with a shaft axis of rotation of the shaft and a magnetic pole of the magnet being oriented orthogonally to the shaft axis of rotation; a motion sensor (202, 222) configured to produce an output signal representing an absolute rotational position of the magnet; and a control system electrically coupled to the motor and the motion sensor, the control system configured to: store an expected rotational position of the motor, determine whether the output signal produced by the motion sensor matches the stored expected rotational position, based on the determination that the output signal does not match the stored expected rotational position, cause the motor to rotate to a rotational position where the output signal produced by the motion sensor matches the stored expected rotational position, receive a control signal indicating a desired mirror position of the mirror, translate the desired mirror position into a desired rotational position of the motor, cause the motor to move to the desired rotational position, and store the desired rotational position as the stored expected rotational position; wherein the control system is configured to determine whether the output signal matches the stored expected rotational position only when the motor is not rotating the mirror. a light source configured to emit a light beam; a mirror configured to controllably deflect the light beam emitted from the light source; a first motion assembly comprising: a motor (208, 228) mechanically coupled to the mirror and configured to rotate the mirror about a mirror axis of rotation (201, 221), where a change in a rotational position of a shaft of the motor relative to a body of the motor causes an equal change in a rotational position of the mirror; characterized by further comprising: a magnet (206, 226) mounted directly to a shaft of the motor, a center of the magnet being aligned with a shaft axis of rotation of the shaft and a magnetic pole of the magnet being oriented orthogonally to the shaft axis of rotation; a motion sensor (202, 222) configured to produce an output signal representing an absolute rotational position of the magnet; and a magnet (206, 226) mounted directly to a shaft of the motor, a center of the magnet being aligned with a shaft axis of rotation of the shaft and a magnetic pole of the magnet being oriented orthogonally to the shaft axis of rotation; a motion sensor (202, 222) configured to produce an output signal representing an absolute rotational position of the magnet; and a control system electrically coupled to the motor and the motion sensor, the control system configured to: store an expected rotational position of the motor, determine whether the output signal produced by the motion sensor matches the stored expected rotational position, based on the determination that the output signal does not match the stored expected rotational position, cause the motor to rotate to a rotational position where the output signal produced by the motion sensor matches the stored expected rotational position, receive a control signal indicating a desired mirror position of the mirror, translate the desired mirror position into a desired rotational position of the motor, cause the motor to move to the desired rotational position, and store the desired rotational position as the stored expected rotational position; wherein the control system is configured to determine whether the output signal matches the stored expected rotational position only when the motor is not rotating the mirror. store an expected rotational position of the motor, determine whether the output signal produced by the motion sensor matches the stored expected rotational position, based on the determination that the output signal does not match the stored expected rotational position, cause the motor to rotate to a rotational position where the output signal produced by the motion sensor matches the stored expected rotational position, receive a control signal indicating a desired mirror position of the mirror, translate the desired mirror position into a desired rotational position of the motor, cause the motor to move to the desired rotational position, and store the desired rotational position as the stored expected rotational position; wherein the control system is configured to determine whether the output signal matches the stored expected rotational position only when the motor is not rotating the mirror. store the desired rotational position as the stored expected rotational position; wherein the control system is configured to determine whether the output signal matches the stored expected rotational position only when the motor is not rotating the mirror.