A method for operating a computed tomograph is provided, wherein an X-ray penetrates an object from different positions, a deposition of an individual dose is effected in at least one part of the object, and an image signal is generated in the detector by way of a transmitted intensity of the X-ray, wherein exposure-related parameters for the respective different positions are individually set such that with respect to a specific position, the share of the associated individual dose is raised if a raising of the individual dose in the specific position brings about a greater improvement in the image quality than in another position, or the share of the associated individual dose is lowered if a lowering of the individual dose in the specific position brings about a smaller deterioration in the image quality than in another position, in order to lower stochastic risks for mutations and uncontrolled cell growth.