There are many ways of dealing with this issue.
I recommend to analyse the 'raw' data, and apply the
radiometric Calibration only at the end.
One possible way to do this is to create a 'dummy'
QLDS, fill the data with unity values, and then
apply the Radiometric Calibration.
In this way, you will have arrays with the correction
factors, that you can inspect and eventually modify.
qlds_calib=copy_qlds(qlds)
NWIN = N_ELEMENTS(QLDS_CALIB.DETDESC)
; fill the data with unity values:
;----------------------------------
FOR IWIN = 0,NWIN-1 DO BEGIN &$
ARRAY = DETDATA(QLDS_CALIB, IWIN+1) &$
ARRAY[*]=1. &$
ST_WINDATA,QLDS_CALIB,IWIN,ARRAY,/NO_COPY &$
ENDFOR
; apply the calibration:
;-----------------------
nis_calib,qlds_calib, /ERGS, /STERAD
; The default units for the returned data are
; PHOTONS/CM^2/SEC/ARCSEC^2, but
; since we used the /ERGS, /STERAD keywords, the
; unints are ERGS/CM^2/SEC/STERAD
;------------------------------------------------
