To point 3, they are absolutely keeping many, many maps of the pixels and dark current for all of their sensors - this is a good picture of the process for a st

To point 3, they are absolutely keeping many, many maps of the pixels and dark current for all of their sensors - this is a good picture of the process for a standard astronomical CCD: https://cdn.nightskypix.com/wp-content/uploads/2020/06/calibration-process-from-DSS.jpg https://cdn.nightskypix.com/wp-content/uploads/2020/06/calib...