[en] Method and apparatus for scanning an object, such as the human body, with radiation utilizes a slit for passing only a portion of scattered radiation from a radiation beam directed through the object to a radiation detector. The slit is arranged with its length extending transverse to the direction of the radiation beam such that the portion of scattered radiation passed by the slit is within a predetermined included angle, preferably within the range of from 60* to 120* and optimally 90*, to produce bands of scattered radiation lying within predetermined solid angles for detection and processing to provide a representation of the path of the radiation beam through the object. By scanning the object with a plurality of parallel radiation beams, which may be provided by translating the x-ray generator, a tomographic cross section of any desired configuration can be obtained