code: public void addImage( CalibrationObservation observation ) {
  		if( imageWidth == 0 ) {
  			this.imageWidth = observation.getWidth();
  			this.imageHeight = observation.getHeight();
  		} else if( observation.getWidth() != this.imageWidth || observation.getHeight() != this.imageHeight) {
  			throw new IllegalArgumentException("Image shape miss match");
  		}
  		observations.add( observation );
  	}
docs: Adds the observations from a calibration target detector
  @param observation Detected calibration points