The pixinsight method is based on the Roddier test. The Roddier test was used to characterize the HST fault in orbit and it is almost as good as a full interferometric test if done carefully. It recreates the Zernike polynomials that describe the wavefront and produces all sort of graphical representations, like synthetic interferogram or wave front error.
The software is free and the learning curve not steep if you understand optics.
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