ISOCAM Interactive Analysis User's Manual Version 5.0 - ISO - ESA

48 CHAPTER 7. CVF OBSERVATION (CAM04)
In contrast to the raster observation in Section 3 we here we have only one CONFIGU-
RATION and consequently only one SSCD.
4. As in Section 3 we need to create a PDS from the SSCD. For CVF data, the equivalent
routine to do this is get sscdcvf. Note that the resulting CVF PDS differs somewhat
from a raster PDS.
CIA> cvf_pds = get_sscdcvf( cleaned_sscd )
5. Now we can calibrate the data in cvf pds. Mostly everything that was discussed in the
previous data analysis examples apply here, with the exception that there is no MOSAIC
for the CVF PDS. As in Section 4.2, this data does not need stabilization correction. Again,
as in the previous data analysis examples, you don’t have to execute all the commands
below at once – you may like to examine the data with x3d between each command.
CIA> corr_dark, cvf_pds
CIA> deglitch, cvf_pds
CIA> stabilize, cvf_pds
CIA> reduce, cvf_pds
CIA> corr_flat, cvf_pds
An additional step that we will perform is the conversion of the EXPOSUREs from ADU
to milli-jansky (mJy).
CIA> conv_flux, cvf_pds
To view the results of your calibration use cvf display.
CIA> cvf_display, cvf_pds
The cvf display (Figure 7.1) window displays an EXPOSURE (co-added IMAGE) and
a plot of the values of a selected pixel throughout the cube of EXPOSUREs. As stated
earlier, the EXPOSURE is derived from the data in a STATE or SCD, and since the CVF
wheel position changed as the STATE changed, then the EXPOSUREs are pictures taken
over a range of wavelengths. This means the plot is a CVF spectrum of the sky covered
by a selected pixel. You can select pixels by right-clicking on the EXPOSURE. The CVF
spectrum is calibrated to flux in mJy per square pixel against wavelength in microns.
6. You may wish to save the results of the data analysis. You can do this with IDL’s SAVE.
CIA> save, file=’cvf_pds.xdr’, cvf_pds
Alternatively you can export each of the CVF EXPOSUREs in .IMAGE to individual
FITS files (see also Section 18.2).