pro background  
;+
;  Name:  ~thirty/background/background.pro
;  
;  Purpose: An example IDL procedure for Leuschner Thirty
;           1. points to Albireo and takes some images (J,K)
;           2. offsets to subtract sky image
;           3. Please run 'openup' before this procedure
;           4. Please focus before this procedure 
;-

ra='19:30:43.3'   ;albireo (HD 183912) J2000
dec='+27:57:35'   ;albireo (HD 183912) J2000
exp_time = 1     ;seconds, exposure time
wait_time = 1    ;seconds, time to wait for telescope to settle
ra_offset = -0.2 ;(degrees) offset amount for subtraction image

;point to albireo ***************************************
print, 'Pointing 
txstring = 'tx point ra='+ra+' dec='+dec+' epoch=2000'
;print, txstring
spawn, txstring

;tracking on *******************************************
spawn, 'tx track on' ;make sure tracking is on

;Aquire K image  ****************************************
print, 'aquiring K image'
spawn, 'tx filter name=Kshort'
wait, wait_time ;seconds, let telescope stop shaking
spawn, 'qimage time='+strcompress(exp_time,/remove)+' outfile=albireo.k.fits'

;Aquire H image  ****************************************
print, 'aquiring H image'
spawn, 'tx filter name=H'
wait, wait_time ;seconds, let telescope stop shaking
spawn, 'qimage time='+strcompress(exp_time,/remove)+' outfile=albireo.h.fits'

;Aquire J image ****************************************
spawn, 'tx filter name=J'
print, 'aquiring J image'
wait, wait_time ;seconds, let telescope stop shaking
spawn, 'qimage time='+strcompress(exp_time,/remove)+' outfile=albireo.j.fits'

;----------------------------------------------------
;Offset for sky
spawn, 'tx offset ra='+ strcompress(ra_offset,/remove) + ' cos'
;----------------------------------------------------

;Aquire J sky image ***************************************
print, 'aquiring J Sky image'
wait, wait_time ;seconds,  let telescope stop shaking
spawn, 'qimage time='+strcompress(exp_time,/remove)+' outfile=sky.j.fits'

;Aquire H sky image ****************************************
spawn, 'tx filter name=H'
print, 'aquiring H sky image'
wait, wait_time ;seconds,  let telescope stop shaking
spawn, 'qimage time='+strcompress(exp_time,/remove)+' outfile=sky.h.fits'

;Aquire K sky image ****************************************
spawn, 'tx filter name=Kshort'
print, 'aquiring K sky image'
wait, wait_time ;seconds,  let telescope stop shaking
spawn, 'qimage time='+strcompress(exp_time,/remove)+' outfile=sky.k.fits'

spawn, 'tx track off' ;make sure tracking is off
;spawn, 'closedown'

star_j = readfits('albireo.j.fits') - readfits('sky.j.fits')
star_h = readfits('albireo.h.fits') - readfits('sky.h.fits')
star_k = readfits('albireo.k.fits') - readfits('sky.k.fits')

tvscl, star_j, channel=3 ;blue
tvscl, star_h, channel=2 ;green
tvscl, star_k, channel=1 ;red

end