Firehose is optimized for point source subtraction.  However it is occasionally useful to look at the 2D sky subtracted frame.  This is handy wen the 1D frame has unusual residuals, or if you would like to generate your own customized routines for extracting extended or multiple sources (the pipeline *can* handle multiple point sources, but requires some hand holding). 

If you would like to access the 2D data, there is an IDL function named "fire_show2D" which will return a 2D array with the sky subtracted data.  This can only be done AFTER normal extraction is attempted, because local sky subtraction is performed at this time.  For example, to look at the sky subtracted image of fire_0123.fits, you can call as follows from the redux directory:

IDL> skysub = fire_show2d('0123')

IDL> xatv, skysub, /block

If you wish to also look at the wavelength map, you can read this in directly from the arc file.  Assuming that file fire_0123 was a long exposure with OH lines for calibration, we read in the arc solution:

IDL> logwv = xmrdfits("Arcs/ArcImg0123.fits.gz")

IDL> wv = 10^logwv

IDL> xatv, skysub, wvimg=wv

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2 Comments

  1. Unknown User (gblancm_1@touchstonenetwork.net)

    fire_show2d returns a blank frame (full of zeros). This is because extension 6 (the mask) in the final multi-extension fits files is set to zero. Is this a bug or did something went wrong in my reduction and the mask should have been set to 1?

    Thanks

  2. Unknown User (nicholas.sterling_1@touchstonenetwork.net)

    I am getting the same error as Guillermo, but only for extended objects in which I used blank sky frames for sky subtraction.  (fire_show2d works perfectly fine for ABBA frames nodded along the slit.)  Has a solution or workaround been found?