The present invention relates to computed tomography X-ray imaging. In order to provide further improved data for reconstruction, a system (10) for computed tomography x-ray imaging is provided. The system has a data interface (12) and a processing unit (14). The data interface provides at least first and second CT x-ray radiation projection data for at least first and second x-ray energy ranges that are different from each other. The processing unit determines a correction for slice normalization and applies equal slice normalization for the first and second CT X-ray radiation projection data to provide the prepared first and second CT X Line radiation projection data is generated. For correction, uniform slice normalization is based on the measurement data of the outer detector element. In addition, the data interface provides the prepared first and second CT x-ray radiation projection data for further processing. In the example, the system is configured as an X-ray source (22) that generates an X-ray beam and an energy-discriminating X-ray detector that simultaneously supplies X-ray radiation projection data separately for at least two different X-ray energy ranges. And a computed tomography X-ray imaging capture device comprising an X-ray detector (26). A computed tomography x-ray imaging capture device captures at least first and second CT x-ray radiation projection data of a region of interest for at least first and second x-ray energy ranges.
