; data_reduction.pro, v1.0.
; R Painter, BSc Project Student '10/'11, 30.03.11.
; Calling sequence: result=data_reduction(data,exposure,mbias,mdark,mflat,mask)

; Fully reduces raw astronomical data in one routine, utilizing the "fixbadpixel.pro" routine as a subroutine.
; Typically completes within 2 minutes, however if a large & complex mask is used (e.g. if masking hot, warm and cool pixels simultaneously), the procedure can take up to 10 minutes per image.
; Input exposure must be in seconds. 
; NB: The exposure time in seconds of a SBIG ST-7E FITS file is able to be read in from its header using the following code: exposure=fxpar(header,'date-obs')

; Steps: Raw -> -master bias -> -scalable master dark -> /normalized master flat -> pixel fix w/ input mask.



FUNCTION data_reduction,data,exposure,mbias,mdark,mflat,mask

data_red=data
exposure_min=exposure/60
mbias=mbias
mdark=mdark
mflat=mflat
mask=mask


; subtract mbias & scalable mdark, ensuring non-zero during subraction phase

data_red=data_red+100000

data_red=data_red-mbias

data_red=data_red-[mdark/(30/exposure_min)]

data_red=data_red-100000


; zero array, if negative values remain

min=min(data_red)

if min lt 0 then begin &$
data_red=data_red-min &$
endif


; divide by normalized mflat

data_red=data_red/mflat


; fix bad pixels, using input mask

data_red=fixbadpixel(data_red,mask)


; restore negative values, if array previously zeroed

if min lt 0 then begin &$
data_red=data_red+min &$
endif


return,data_red
end