The reproduction parameters of an radiographic are presented by those details of the various visualised objects which are important for diagnosis. These parameters determine the required technical quality. The following factors are suitable for assessing the technical quality of the radiographs: medium optical density, contrast, resolution, peak voltage, exposure time and exposure dose. The physician himself is expected to maintain a close watch on the quality of his x-ray examinations. The following measures are conductive to this end: 1. comparison of the current patient radiographs with the standard x-ray visualisations as seen in routine practice 2. control of the processing technique with test films, and 3. checking on the proper functioning of the x-ray equipment by means of a small phantom. Over and above this, the x-ray equipment should be checked for its efficiency status in yearly intervals by means of measurements effected with a standard phantom by an external institution.