Data Reduction Frequently Asked Questions
The response curve leaves residual instrument features in my science.
Changes in the spectral energy distribution between the observations of the flat field for the flux standard star and that for the science data can cause problems in flux calibrations. To can be avoided by flat-fielding the flux standard star spectrum with the same flat field as is used for the science data. This can be done setting UseResponseFlat to false in the Flat Strategy actor of Reflex.