Photosphere weighted magnification distortion acting over the light curves, computed at the position of image 1. The distortion is plotted as a function of the FWHM of the expanding photosphere, and each realization has been re-scaled to the moment where the SN reaches maximum luminosity (FWHM ≈ 1.2 × 10⁻³ pc). The green region marks the 68% confidence interval from over 7 million simulated distortion curves. The colored dotted curves show 35 individual random realizations out of the 7 million. The thick black curve corresponds to the average of the 7 million curves.