Methods and apparatuses process sensing signals. A method for redrawing a sensing image when a range is or has been changed, according to one aspect of the present invention, records the sensing image and outputs the sensing image to a display; records additional information displayed upon a screen and outputs the additional information to the display; computes a new image from the recorded sensing image using an image manipulation computer function, so that the computed image fits a new scale of the changed range, and recording the computed image; and computes changes to the recorded additional information to adjust the additional information to the new scale of the changed range, and records the computed additional information.