1. A method for establishing a magnetic resonance system actuation sequence, having at least one radiofrequency pulse train to be emitted by a magnetic resonance system into a measurement region, the method comprising: acquiring a first number of field distribution maps for slices of the measurement region; and establishing the at least one radiofrequency pulse train on the basis of the first number of field distribution maps, wherein the acquisition of the first number of field distribution maps is brought about on the basis of an acquisition scheme for a first number of field distribution representation slices that represent field distribution maps for a second number of slices in view of a predetermined optimization criterion, wherein the first number of field distribution representation slices is less than the second number of slices, and wherein a number of field distribution representation maps are established on the basis of the first number of field distribution maps and in accordance with a predetermined optimization criterion, and the at least one radiofrequency pulse train is established on the basis of the field distribution representation maps, wherein the number of the field distribution representation maps is less than the first number of field distribution maps.