flat-fielding.html

Flat-field the Science Exposures

Before running biasflat, make sure the proper parameters are set in the parameter file:

editpar biasflat
./biasflat.par

type q to end

dewar                      E2V       dewar definition file
speed                     slow       readout speed
flat_file                 none       flat field frame
bias_file                 none       bias frame

After the parameter file is set, we can run the biasflat command to flat-field and subtract the bias from the science exposures:

biasflat -f ift0011_flat ift0009
biasflat -f ift0011_flat ift0010

These commands generate ift0009_f_cX.fits and ift0010_f_cX.fits, respectively. See Figure 8 for a section of one of the flat-fielded and bias-subtracted science exposures. Now we can move on to sky-subtraction.

**Figure 8:** Section of flat-fielded science exposure generated by biasflat.

Next: Run Sky-Subtraction on the Science Exposures Up: Reducing the Spectra Previous: Creating Spectroscopic Flat Fields Contents

Edward Villanueva 2014-08-27