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STSDAS
About STSDAS

The Space Telescope Science Data Analysis System (STSDAS) is software for calibrating and analyzing data from the Hubble Space Telescope (HST). STSDAS includes the same calibration routines as are used in the STScI operational data processing pipeline, as well as general-purpose tools and enhancements to the Image Reduction and Analysis Facility (IRAF).

IRAF provides the user interface (command language, or CL) and general purpose graphic and image display facilities. Because STSDAS is layered on IRAF, the system runs on any computing platform for which an IRAF port is available, including most Unix systems. STSDAS can also be used with PyRAF.

STSDAS Package Organization

Programs in STSDAS are called tasks. Tasks are grouped by function into packages, which can themselves be further grouped into packages.

analysis Data analysis packages.
dither Dithered image combination.
fitting Curve fitting tools.
fourier Fourier analysis.
gasp Access the HST Guide Star Catalog on CD-ROM.
isophote Elliptical isophote image analysis.
nebular Tasks for analyzing nebular emission lines
restore Deconvolve or filter 1- or 2-dimensional images.
statistics Statistical analysis software.
contrib User-contributed software.
redshift Tasks for determining redshifts and dispersions.
spfitpkg Tasks for fitting spectra with non-linear chi-square minimization
vla Spectral image reduction for VLA data.
fitsio FITS input/output for Space Telescope data (images and tables).
graphics Graphics and image display packages.
sdisplay Image display package for SAOImage display device.
stplot General plotting utilities.
hst_calib HST Science Instrument calibration packages.
acs Tasks for calibrating ACS data.
ctools General calibration tools.
foc Tasks for calibrating FOC data.
focprism FOC prism package.
fos Tasks for calibrating FOS data.
spec_polar Tasks for reducing and analyzing FOS polarimetry observations.
hrs Tasks for calibrating HRS data.
nicmos Tasks for calibrating NICMOS data.
mstools General-purpose tasks that handle NICMOS IMSETs.
paperprod Tasks for generating paper products.
stis Tasks for calibrating STIS data.
synphot Tasks for synthetic photometry and modelling instrument response.
wfpc Tasks for calibrating WFPC and WFPC-2 data.
w_calib Tasks for deriving the WF/PC instrument calibration.
playpen Miscellaneous experimental tasks.
sobsolete Package of tasks that have been retired.
foccs OC calibration software package.
focgeom FOC geometry package.
focphot FOC photometry package.
focutility Obsolete FOC utility package
hsp Tasks for calibrating HSP data.
registration Compute registration parameters and resample unaligned data files
testdata Tools for creating artificial images.
timeseries Time series photometry data reduction and analysis.
y_calib Tasks supporting the FOS calibration process.
z_calib Tasks supporting the HRS calibration process.
toolbox General tools packages.
convfile Reformat images from one machine type to another (VAX <-> Sun only).
headers Tools for modifying image headers.
imgtools Tools for manipulating & examining images and bad pixel lists.
mstools Tasks to handle STIS/NICMOS IMSETs.
tools Generic data handling and utility tools.
ttools Table manipulation tools.

You can see an alphabetical list of task names as part of our online help system.

More complete documentation can be found in the HST Data Handbook, which includes an overview of how to use STSDAS to accomplish basic tasks and how to use tasks that are specific to the HST instruments. The STSDAS User Guide was last updated in 1994(!), but does contain information on some of the older packages in STSDAS.