12 If the camera calibration is performed while the target is dirty, the measurement error may deteriorate. If the camera calibration target is dirty, wring out a wet towel, wipe it clean, and dry it with a soft cloth before performing the calibration. If the camera calibration is performed while the 3D Vision Sensor is dirty, the measurement error may deteriorate. If the 3D Vision Sensor window surface is dirty, wring out a wet towel, wipe the dirt off, and dry with a dry cloth. When placing the camera calibration target, place it slowly so that your hands do not get caught on the floor.