A method and an apparatus are disclosed for determining the effective count rate of photons in a combined MR/emission tomography recording. In at least one embodiment, the method includes capturing MR signals with an MR apparatus in an MR/emission tomography device for producing an MR recording of an examination object with a number of tissue types, each having a specific MR parameter; associating a number of emission tomography attenuation coefficients with the number of tissue types as a function of the MR parameter by way of an association unit, so that one emission tomography attenuation coefficient corresponds in each instance to at least one of the tissue types in the examination object; capturing photons in the examination object with an emission tomography apparatus in the MR/emission tomography device for producing an emission tomography recording; and weighting the emission tomography recording with the emission tomography attenuation coefficients by way of a correction apparatus for determining the effective count rate in the number of tissue types and for producing a corrected emission tomography recording.