These are divided into two proposals: the first to obtain a large number of Earth cals (observations of the bright Earth) in just four filters and the second to obtain a small set of Earth cals in a larger number of (primarily narrowband) filters. The superflats generated from the first proposal's data map the OTA illumination pattern and are combined with the thermal vacuum test data flats (and possibly cal-channel flat fields) to provide a set of flat fields which remove both the OTA illumination pattern and the pixel-to-pixel response of the cameras. The images from the second proposal will also help determine the OTA illumination pattern, but used in conjunction with the Earth superflats (and cal-channel flats), will provide delta corrections to the superflats applicable to the narrow- and medium- band filters.
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