In a magnetic resonance apparatus and operating method therefor, movement compensation during raw data acquisition is accomplished by operating the data acquisition scanner to acquire data from a reference navigator volume at a first point in time, using a simultaneous multi-slice technique with a first acceleration factor and a first number of first slice groups, and to acquire data from a navigator volume at a second point in time, also using a simultaneous multi-slice technique, but with a second acceleration factor and a second number of second slice groups, with the first and second acceleration factors being equal. Movement information is determined from the reference navigator volume and the navigator volume, describing movement of the patient occurring between the first and second points in time. Data acquisition parameters of the scanner are set after the second point in time, dependent on the movement information, for acquiring further magnetic resonance data.