Wavelength calibration


ATTENTION: in the following we have chosen the 2.06163 µm argon line for the wavelength calibration. Any other line can be used for calibration.  The appropriate exposure time and argument of the grifsetup command must then be used. Available lines include 2.09861 Argon (15 s) and 2.19025 Kr (30s).

- Choose Kprime filter
- From the DetI GUI, type "etime 15" (if there are 2 argon lamps in the  Gumball) or "etime 10" (if there are 3)
- On the GriF Xterm, type "grifsetup clean" to switchy off all Gumball lamps
- On the GriF Xterm, type "grifsetup argon" to switch on the Argon Gumball lamps
- On the GriF Xterm, type "fp -wave 2.06163 -1 -nstep 7" to execute a 7-step scan of the He I line at 2.06163 µm
- When the scan is finished, on the IDL Xterm, in IDL, execute the command "calc_const_fp" to get the observed BCV profile. The program computes "BCV_cal", the BCV corresponding to 2.06163 µm
- On the GriF Xterm, type "setcalib 2.06163 BCV_cal", where BCV_cal is the value given by the IDL program (choose the one with the lowest chi2 value)
If you are going to then observe a scientific object, don't forget to type "grifsetup clean" and "grifsetup object"