An x-ray system, such as a computed tomography system, has an x-ray source, a projection detector arrangement associated with the x-ray source for the acquisition of projection data of an examination subject, and a monitor detector that measures current dose measurement data of the x-ray radiation. The monitor detector is designed and arranged to detect a portion of the x-ray radiation that does not travel through the examination subject. The monitor detector is formed as an energy-resolving detector. Furthermore, a method for the acquisition of projection data of an examination subject a method to generate image data make use of such an x-ray system.
