[Considerations on direct magnification in radiology].

Magnification in mammography is changing for the worse if the goal is to show objects (microcalcifications) which are smaller or of the same size as the focal spot of the x-ray tube. A radiograph without intensifying screens offers more information than a standard screen-film mammography. Magnification yields an easier visibility of microcalcifications larger in size than the focal spot; there are the disadvantages of the microfocal tube. With the intensifying screens now in use the most profitable focal spot size in mammography seems to be 0.4-0.6 mm.