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1. 10W QTH lamp for flatfielding medium resolution (R=200-2000) 0.8-2.5um modes
2. 0.1W incandescent lamp for flatfielding low resolution (R=25-250) 0.8-2.5um prism mode
3. IR (1200K) lamp for flatfielding medium resolution (R=250-2500) 1.9-5.5um modes
4. Argon lamp for wavelength calibration of all spectral modes (lines are visible in the range 0.8-4um)

For wavelength calibration at wavelengths longer than 3.6um the
spectral extraction program 'Spextool' uses sky lines.
	
The lamps feed an integrating sphere the output of which is imaged
onto the telescope focal plane inside the cryostat at the same optical 
speed as the incoming telescope beam (f/37). A pick-off mirror immediately
above the cryostat window can moved into position for lamp calibrations
when required.
	
SpeX is a big instrument (about 1100 lbs) and is mounted at cassegrain
focus. Internal flexure is about 1-2 pixels (depending on direction)
in wavelength over about 60 degrees of motion (eg. from 2 airmasses to
zenith). To reduce this movement to 0.25-0.5 pixels calibrations should
be done every 15 degrees (roughly once per hour for long integrations).
To ensure good telluric cancellation, object and standard stars need to
be taken close in airmass (difference less than 0.05) and time. 
Standard practice is to take one set of calibrations per object-standard
pair. The effects of flexure may also be removed in the data reduction
process by shifting the standard spectrum in wavelength relative to the
object so that telluric features register (this shift should be done
in pixel space and not in microns). 
	
DO NOT EDIT THE CALIBRATION MACRO FILES without first consulting
with your support astronomer. 
	
Flatfielding and wavelength calibration takes about a couple of
minutes. The only observer interaction is to start the macro file
which automatically acquires and saves the calibration data and returns
the instrument to the observing configuration. To keep the SN high in
all modes ITIMES depend on observing mode and slit width. Observers
should select the macro which corresponds to spectral mode and slit
width they are using:
	
0.8-2.5um XD modes (SXD)
cal_sxd_0.3  (0.3arsec slit etc.)
cal_sxd_0.5
cal_sxd_0.8
cal_sxd_1.6
cal_sxd_3.0
	
0.8-2.5um prism mode (LowRes)
cal_prism_0.3 
cal_prism_0.5 
cal_prism_0.8 
cal_prism_1.6 
cal_prism_3.0 
	
1.9-4.2um XD modes (LXD_1.9)
cal_lxd_1.9_0.3
cal_lxd_1.9_0.5
cal_lxd_1.9_0.8
cal_lxd_1.9_1.6
(Wider slits cause saturation at 0.4V detector bias, ask
support astronomer about increasing bias or decreasing
slowcounts)
	
2.1-5.0um XD modes (LXD_2.1)
cal_lxd_2.3_0.3
cal_lxd_2.3_0.5
cal_lxd_2.3_0.8
(Wider slits cause saturation at 0.4V detector bias, ask
support astronomer about increasing bias or decreasing
slowcounts)
	
2.3-5.5um XD modes (LXD_2.3)
cal_lxd_2.3_0.3
cal_lxd_2.3_0.5
cal_lxd_2.3_0.8
(Wider slits cause saturation at 0.4V detector bias, ask
support astronomer about increasing bias or decreasing
slowcounts)
	
Single order long slit modes use the equivalent XD macro.
For example, the single order mode using the Long 5 filter
(3.59-4.14um) and a 0.5 arcsec-wide slit uses the cal_lxd_1.9_0.5
macro since this macro flatfields for the range 1.9-4.1um
(cal_lxd_2.3_0.5 could also be used). For wavelengths longer
than 3.6um sky of object lines must be used for wavelength
calibration.

Running macros instructions.  	
Always check that the macro runs correctly by monitoring the data
in DV as it is taken. A macro may be aborted by clicking
on the red Stop in the MACRO window, followed by the red STOP at
the top of the XUI screen. However, aborting a macro
will leave the instrument in the configuration it was in
at the point the macro was stopped so be very careful
when restarting.
	
If a particular macro file is to be used alot, it is
slightly more efficient to set it up as a FUNCTION. 
For an example, click here.  
	
Macros for flatfield and wavelength calibration are
stored in bigdog:/home/bigdog/macro/bigdog
	
Examples:
	
cal_sxd_0.5'
------------------------------------------------------------------------
#
# Flat and line cal for SXD and 0.5" slit
#
ParameterSave
AutoSave On
Lamp Qth On
CalMir In
Itime 1.0
Coadd 5
Cycles 5
ObsMode 0
Object QTH Lamp
Comment Flat
filename flat
m.wait 20.0
Go
Lamp Qth Off
Lamp Ar On
Itime 1.000
Coadd 10
Cycles 2
ObsMode 0
Object Argon lamp
Comment wavelength cal
filename arc
m.wait 5.0
Go
ParameterRestore
isready
#end of cal macro
	
	
	
cal_lxd_1.9_0.5'
-----------------------------------------------------------------------
#
# Flat and line cal for LXD_2.3 and 0.5" slit
#
ParameterSave
AutoSave On
CalMIr In
Lamp Ar On
ObsMode 0
Itime 2.0
Coadd 10
Cycles 1
Object Argon
Comment arc on
filename arc
SubAB On
Go
Lamp Ar Off
ObsMode 1
Itime 2
Coadd 10
Cycles 1
Object Argon
Comment atc off
filename arc
Go
Lamp QTH On
Lamp IR On
m.wait 120.0
SlowCnt 3
Itime 0.24
Coadd 10
Cycles 5
ObsMode 0
Object IR lamp
Comment Flat
filename flat
SubAB Off
Go
ParameterRestore
isready
SlowCnt 20
#end of cal macro

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