Photon transfer curve for the IMX411 sensor obtained from statistics build from 6 × 6 binned superpixels over the first third of the scale. Top: the three colors correspond to three independent datasets obtained with different illuminations, exposure times, and numbers of images (see Table 3). The black solid line presents the linear relation from Eq. (A.9) using the best-fit gain value. Middle: residuals to the linear model. The dashed black lines denote 1% variations of the integral gain. Bottom: residuals to the full model, including the effect of a 512-bit periodical DNL with 0.65 ADU of amplitude, and provision for curvature of the PTC due to residual influence of a brighter-fatter effect in the binned superpixels.