Calibration factors returned by PODC for the 110 calibration units corresponding to the ungated windows for the faintest sources (fainter than G_mag ~16). The calibration factors for the calibration unit corresponding to AF8, row 2 in the following field-of-view (FFoV) is shown in red. The time interval covers the range of IDT runs from 1046 to 4724 used in this paper, and is expressed in days in on-board mission time (OBMT). Excursions in the daily measured calibration factor can and do occur, these can result from large numbers of cosmic rays/charged particle events as well as micrometeroid hits. Insert lower left: (indicated by magenta arrow) excursion which occurred roughly 2 days after the CME X9.3 of September 2017. Insert lower right: close-up of the more typical stable behaviour of the calibration factor derived by PODC. We note the jump around OBMT 1861.9 is a refocusing of both FOVs.