In a method to determine an MR system-dependent phase information of a phase value in an MR phase image data set, initial variances are associated with image points of a first phase image data set, and for an additional phase image data set, a phase value and a variance of the phase value for the image points of the additional phase image data set are estimated by a linear transformation of the first phase image data set. The additional image data set is calculated by weighted addition of the phase values of the first phase image data set with the estimated phase values, with the weighting of the two phase values taking place in the addition dependent on the variance belonging to the respective phase value.