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%++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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%.COPYRIGHT (c) 1994 European Southern Observatory
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%.KEYWORDS MIDAS, help files, FLAT/MOS
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%.PURPOSE On-line help file for the command: FLAT/MOS
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%.VERSION 1.0 04-AUG-1994 : Creation, SM
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%----------------------------------------------------------------
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FLAT/MOS 20-SEP-1994 SM
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FLAT/MOS [obj] objf [ff] [mos] [normff] [order] [method]
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normalize MOS flat-field frame and divide object by it
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Normalize MOS flat-field frame and divide object frame by it
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Syntax: FLAT/MOS [obj] objf [ff] [mos] [normff] [order] [method]
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Session keyword: OBJECT
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objf = flat-field corrected object image
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mos = Input table with slitlet positions
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normff = normalized flat field
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Session keyword: NORMFLAT
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order = order of fit, or width of median filter
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Session keyword: FFORD
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method = smoothing method (median or polynomial)
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Session keyword: NORMMET
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This command will fit a polynomial of order ORDER
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to the flat FF (resp. smooth FF with a median filter
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of width ORDER), and divide FF by the fitted resp.
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smoothed image, thereby creating the normalized flat
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NORMFF. This normalized flat should now only show
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the high-frequency pixel-to-pixel variations of the CCD
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sensitivity. Then the object frame OBJ is divided through
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the normalized flat. OBJF holds the output of this action.
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FLAT/MOS object objf flat mos normflat 3 poly
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Fits a 3rd order polynomial to the spectral signature of flat.bdf
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and thereby normalizes it to normflat.bdf. It then divides object.bdf
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by normflat.bdf and stores the result in objf.bdf.