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Knowledgebase: IRS
In SMART's interactive extraction mode, the size of the extraction window appears to be insensitive to the manually defined extraction width.
Posted by z-Vandana Desai on 01 December 2008 03:34 PM
This is a known problem and is being fixed.

It has been reported by a user that selecting 'fixed column' extraction in the 'interactive extraction' will perform a fixed column extraction and will use the user-defined extraction width if you manually set the user-parameter !sm_fwhmfactor=+1 in the calibration setup. Or alternatively this can be done by typing !sm_fwhmfactor=1.0 at the IDL prompt, within the SMART environment. You will need to set this back to -1 when doing any other type of extraction. The effect of doing a fixed column extraction with !sm_fwhmfactor=-1 is to use the standard SSC-defined extraction windows (i.e. 4.25 pixels wide at 16 um in LL2), but without scaling with wavelength, i.e. a fixed width of 4.25 pixels for LL2.