1. A method for generating a selective magnetic resonance (MR) image, comprising: acquiring raw data for each of a first MR image and a second MR image by operating a magnetic resonance data acquisition unit by: (a) activating at least two phase coding gradients in respective spatial directions with a gradient system of the data acquisition unit, (b) after the activated phase coding gradients achieve a full strength, exciting nuclear spins in the examination subject radiating a non-slice-selective RF excitation pulse with an RF transmission/reception system of the data acquisition unit, (c) after a time TE 1 following the radiated excitation pulse, acquiring first echo signals with said RF transmission/reception system and storing said first echo signals as raw data points in an electronic memory organized as k-space along a radial k-space trajectory in k-space that is predetermined by the strength of the phase coding gradients, (d) inverting said at least two phase coding gradients, (e) after a time TE 2 following the radiated excitation pulse, acquiring said second echo signals with said RF transmission/reception system and storing said second echo signals as raw data points in k-space along a radial k-space trajectory that is determined by the strength of the phase coding gradients, (f) repeating (a) through (e) with respectively different phase coding gradients in each repetition until k-space corresponding to the image area is read out in a first region of k-space along radial k-space trajectories, depending on said time TE 1 and said time TE 2 , and (g) reading out a remainder of k-space that corresponds to the imaging area, said remainder not being filled by said first region and including at least a center of k-space, in a read out procedure that is different from (a) through (f), and storing all data points read out in (f) and (g); in a processor having access to said electronic memory, reconstructing a first MR image from said first echo signals and reconstructing a second MR image from said second echo signals, in said processor, for each image point of said first and second MR images, calculating a time constant that corresponds to tissue imaged at the respective image point, dependent on respective intensity values of corresponding image points in said first and second MR images; in said processor, comparing each calculated time constant with at least one threshold, to obtain a comparison result; in said processor, dependent on said comparison result, associating a weighting factor with each image point; and in said processor, generating a selective MR image by processing the respective intensity values of the image points of at least one of said first MR image and said second MR image with the respective, associated weighting factors, and making said selective MR image available in electronic form at an output of said processor.