In a method and apparatus for providing a visualization image and a reference image for a patient, with only one reconstruction being implemented, raw scan data from the patient are reconstructed into a visualization image, and the reference image is generated, without another reconstruction, by applying a filter to the visualization image to obtain a simulated reference image, using a value of a filter parameter that is specific for the patient. The patient-specific filter parameter is determined by comparing image-derived properties of an accessed, previously-reconstructed reference image and the reference image, and the filter parameter is adapted to reduce differences in the image-derived properties of the respective images.