X-ray diagnostic system comprising tomographic apparatus

An x-ray diagnostic system comprising tomographic apparatus having path selection means for the selection of the path of movement, a photographic exposure unit comprised of an x-ray tube and an image layer carrier, an x-ray diagnostic generator for supplying a high voltage for energizing said x-ray tube and having means (8, 9) for the selection of exposure parameters for the photographic exposure unit to provide for an x-ray exposure during a photographic exposure time which is a function of said exposure parameters, characterized in speed controlling means for causing said photographic exposure unit to begin traversing the path of movement selected by said path selection means during an initial time interval at a given running speed selected to complete traverse of the path in a total running time equal to the expected exposure time, control signal forming means (16, 29) coupled with the tomographic apparatus for generating a control signal during said initial time interval as a function of the exposure parameter that determines the exposure time, and comparator means (25) having one input coupled with said control signal forming means for receiving a control signal generated during said initial time interval and a second input for receiving a motor signal indicating the actual speed of the exposure unit said comparator means (25) having an output for connection with said speed controlling means and being operable to compare the control signal with the motor signal and to control said speed controlling means in accordance with any deviation of said control signal relative to said motor signal to adjust the running speed of the photographic exposure unit along the selected path after the initial time interval such that the actual total running time of the photographic exposure unit along the selected path will substantially equal the photographic exposure time based on measurement of said photographic exposure parameter.