The present application relates to a method and an apparatus for determining a wavefront of a massive particle beam, including the steps of: (a) recording two or more images of a reference structure using the massive particle beam under different recording conditions; (b) generating point spread functions for the two or more recorded images with a modified reference image of the reference structure; and (c) performing a phase reconstruction of the massive particle beam on the basis of the generated point spread functions and the different recording conditions, for the purposes of determining the wavefront.