calib_blue -- acquire calibrations for blue-ish central wavelength
settings on DEIMOS
This is a script to run arc line and internal flat lamp
calibrations for DEIMOS when observing in the blue. This
script was tweaked for use with the 900ZD grating at a central
wavelength of 5500 Angstroms. It takes separate arc and flat
exposures for the red chips and the blue chips. The red-chip
arc and flat images are not appropriate for the blue side and
For arc lamp exposures, the red chips use the standard
combination of lamps used in the main calibration script. The
arc exposure for the blue chips use a combination of lamps
optimized to get the most lines in the blue. Some lamps are
turned off during the exposure so that they do not saturate.
The active lamps will not be recorded properly in the FITS
header. The user must modify the FITS header to reflect all
five lamps that were on at some point in the exposure: Hg Cd
Zn Ar Kr. If the spec2d pipeline is used for data reduction,
separate arc exposures may be specified in the plan file using
the BLUEARCNAME and REDARCNAME keywords.
For flat field exposures, the script acquires three images for
the red side. Because the throughput is very low near 4000
Angstroms, the script acquires six images for the blue side.
These exposures will saturate the red side. As written, the
spec2d pipeline will not accept separate red and blue flat
field images. However, it is reasonably easy to modify the
read_planfile.pro and deimos_mask_calibrate.pro files to
accept different images.
The script requires about 23 minutes per mask. If short on
time, then the time to warm up lamps can be reduced in some
calib_blue mask1 mask2 mask3 ...
maskN = mask names for which to acquire calibration images
0 = normal completion
1 = wrong number of arguments
The shell script calib_blue
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Last modified: Mon Aug 1 09:15:27 2011