Example of linear flux definition using ramps acquired in UTR(394). Fit performed using 76 frames $S_{\text{lin}}^{(76)}$ and 394 frames $S_{\text{lin}}^{(394)}$. The difference per pixel of first-order coefficients was computed and the relative differences between the median signals per detector are shown for two detectors: low persistence SCA18452 (blue points) and higher persistence SCA18267 (red squares).