An image sensor having a two-dimensional array of pixel sensors, a layer of scintillation material, and a controller is disclosed. The layer of scintillation material is adjacent to the two-dimensional array, the scintillation material emits light in response to x-rays impinging thereon. The pixel sensors detect this light. The controller reads out data stored in the two-dimensional array of pixel sensors and forms an image therefrom. The controller corrects the data for errors resulting from x-rays that generate electrons that are stored in the pixel sensors in the process of forming the image. In one aspect of the invention, the controller forms the image by causing the two-dimensional array to form a plurality of frames, each frame includes a measurement of a charge stored on each photodiode during a preceding time period. The controller selectively combines data from the frames to form the image.