1. A method for acquiring a magnetic resonance measurement data set of a respirating subject, comprising: operating a magnetic resonance data acquisition unit, in which a respirating subject is located, to acquire a plurality of magnetic resonance data subsets; entering the plurality of magnetic resonance data subsets into an electronic memory representing k-space, wherein k-space is comprised of a plurality of segments, and entering the respective magnetic resonance data subsets individually into respective k-space segments; also operating said magnetic resonance data acquisition unit to implement a navigator data acquisition, before and after each of said magnetic resonance data subset acquisitions, that identifies a respiratory position of the subject and a respiratory phase of the subject; and in a processor, using the respiratory position and the respiratory phase for the respective navigator data acquisitions for each of the magnetic resonance data subsets, automatically including or not including a respective magnetic resonance data subset in a final magnetic resonance data set from which a magnetic resonance image is to be reconstructed, and making said final magnetic resonance data set available in electronic form at an output of said processor.