MT9-B reconstructions. The graphs show the roll, yaw and tilt measured by the sensor, compared with the same measurements deduced from the controlling mechanism. The left column shows examples of the worst drift in each angle and the right column shows examples of the best. Graphs (a-c) were derived form the roll-yaw experiment, which had some nearby ferromagnetic material. Graphs (d-f) are from the tilt-yaw experiment, where the ferromagnetic material was more distant.