1. A method for operating a magnetic resonance imaging apparatus having an antenna array comprised of a plurality of reception coils for simultaneously receiving magnetic resonance signals from a subject, each of said coils having a coil sensitivity, comprising the steps of: acquiring a plurality of sets of reference data of a subject by executing a series of reference scans with a first sequence kernel optimized for coil sensitivity calibration; obtaining a plurality of sets of image data of said subject by executing a series of accelerated image scans with a second sequence kernel, different from said first sequence kernel, optimized for imaging, by obtaining magnetic resonance signals from said subject simultaneously with multiple reception coils in said plurality of reception coils; for each coil, calculating a coil sensitivity map from said sets of reference data; and reconstructing an image of said subject by operating on said sets of image data with a parallel reconstruction algorithm employing said coil sensitivity maps.