STScI Logo

Hubble Space Telescope
Software Tools

Tools for planning ACS observations
ACS/WFC CTE Correction Calculator This tool corrects ACS/WFC aperture photometry for CTE losses using the most recent formula from Chiaberge's ISR 2012-05. It is only calibrated for photometry obtained after SM4 in May 2009. For pre-SM4 data, please see Chiaberge et al. 2009 (ISR 2009-01), or use pixel-based CTE-corrected files obtained from MAST.
ACS Exposure Time Calculator (ETC) An on-line tool useful to predict the signal-to-noise for various observing modes, once the characteristics of the source are known.
Software for analysing ACS data
Additional applications specific to the ACS are:
Pixel Based CTE Correction Tutorial on how to run the CTE code
Destriping Tutorial Tutorial on how to run the Destriping Code
STSDAS the IRAF package containing CALACS, which is used to process ACS data
AstroDrizzle the PyRAF script that performs automated image registration, cosmic-ray rejection and final combination with drizzle, all in a single step, with user-adjustable parameters to provide more flexibility if desired.
OTFR "on the fly reprocessing" is run automatically on data requested from the archive
AXE For ACS slitless modes, a dedicated package has been developed by the ST-ECF to enable automatic and reliable extraction of large numbers of spectra.
Requests for ACS data from the HST Archive always return data reprocessed with the current version of CALACS and the best available reference files. In most cases it is easier to let the OTFR pipeline reprocess data for you. If standard pipeline processing is inadequate, however, CALACS may be downloaded and run locally.