The invention relates to a computer-implemented method for operating a magnetic
resonance device (20) during an acquisition process according to an
acquisition protocol, which uses at least one
magnetic resonance sequence in an acquisition period and comprises radio-frequency pulses (2, 4) preceding acquisition periods (3), wherein - for at least some of the high-frequency pulses (2, 4), at least one measured value is recorded in a measuring period (5) describing the reverse power reflected back by a coil element used to output the high-frequency pulses (2, 4), so that a
time series (6, 7, 8, 9) of measured values is created over the recording period, - the
time series (6, 7, 8, 9) of measured values for detecting an occurring movement of the recorded examination object, which is described by movement information, is evaluated in an evaluation step (S3), and - the movement information is used to control the recording process and / or in a reconstruction of an image
data set from recorded magnetic
resonance data, characterized in that before the evaluation step (S3), in a preprocessing step (S2), the
time series (6, 7, 8, 9) is used to at least partially remove the property from the time series (6, 7, 8, 9) using at least one piece of
background information which describes a non-movement-related, expected property of the time series (6, 7, 8, 9).