PSF improvement scenario. The observed exposure contains 2050 stars, of which 50 have complementary spectral information (in yellow) and 2000 do not (in blue). An approximate PSF model is trained from 50 stars with known SEDs. The approximate PSF is used in the context of the PSF-aware classifier to spectrally classify the remaining 2000 stars. The classified stars are assigned a SED template and can be used to train an improved PSF model.