Time evolution of the LS calibration standard deviation (sigma) and zero point for the preceding FoV (panels 1 and 2, respectively) and following FoV (panels 3 and 4, respectively) for each CCD row. All solutions only consider the ungated AF1 observations acquired with window class 1 (corresponding approximately to 13 < G < 16). The two decontaminations are clearly visible in both FoVs as a major discontinuity in the calibration zero point. The first refocus can be seen as a very small step in the zero point for the following FoV, whereas the second refocus is more visible as a slightly larger step in the zero point for the preceding FoV. Additional features visible in both the standard deviation and zero point are discussed in the text.