2025/05/10 CHARIS PDI Calibration Data

Raw CHARIS data from the 2025/05/10 PDI calibration measurement. The calibration files necessary for cube extraction are at the end of the list of files, including wavelength calibration flats, darks, pinholes, and non-PDI flat fields. The remaining files are the flat-field data taken with the Wollaston prism while modulating polarmetric components. These data are labeled with OBJECT='PDI FLAT'. Polarized signal was generated using a halogen lamp with a fixed (horizontal) polarizer. The image rotator was modulated to 8 different positions from 45 deg to 132.5 deg (typical observations take place ~90 deg). The HWP was modulated at each image rotator position between 0 and 90 deg (inclusive, 9 files per image rotator angle). The image rotator angle can be retrieved from `D_IMRANG` (note you should round this number off to 1 decimal point) and the HWP angle can be retrieved from `RET-ANG1` or `RET-POS1` (equivalent in this context). Note: the CHARIS data was taken while a telemetry process on SCExAO head died, and the actual waveplate unit (WPU) telemetry was not recorded in the FITS headers (nor was any of the SCExAO bench telemetry, the `X_` keywords). I have manually edited the files to include a subset of the WPU telemetry for the HWP angles.