Figure 6. The FI and BI data are compared.
The coarsely binned data are from the FI chip in the C-K region where
the overall QE is quite low, so the data are heavily binned. Nevertheless,
there is a distinct edge that is not taken into account in the current
OBF filter model. The data agree reasonably well with the BI results,
after accounting for a systematic QE difference of 20%, except that
the BI data are somewhat lower than the FI data near 0.29 keV.