The invention describes a method for automatic motion detection in medical image-series, comprising the steps:- providing a dataset (D) of a series of images (I1, I2, I3), wherein images (I1, I2, I3) of a similar region of interest are recorded at consecutive points of time,- calculating localization data (LD) of a target (T) by localizing the target (T) in the images (I1, I2, I3) of the dataset (D) and calculating the position of this target (T) in these images (I1, I2, I3),- calculating movement data (MD) of the movement of the target (T) on the basis of temporal adjacent images (I1, I2, I3) based on the localization data (LD).The invention further describes a related system, a related control device and a related medical imaging system.