The present invention relates to a radiographic imaging apparatus and a corresponding radiographic imaging method. The proposed apparatus comprises an X-ray source (20, 108) and a photon counting X-ray detector (40, 110). The X-ray source (20, 108) comprises a rotary X-ray anode (23) having a number of radial slits and a target layer provided on a surface of said rotary X-ray anode in between said radial slits for emitting X-ray radiation when hit by said electron beam. The said photon counting X-ray detector (40, 110) comprises a persistent current sensing and correction unit (70) for sensing a persistent output current in a blanking interval during which no X-ray radiation is emitted by said X-ray source and for using the sensed persistent output current to correct a detector signal in a subsequent measurement interval during which X-ray radiation is emitted by said X-ray source.
