The DrizzlePac Handbook

Version  –  2021
PDF version

DrizzlePac Handbook

Table of Contents

User Support

  • Please contact the HST Help Desk for assistance. We encourage users to access the new web portal where you can submit your questions directly to the appropriate team of experts.

Additional Resources

Information and other resources are available from the STScI DrizzlePac website.

For installation help, coding examples, and additional documentation, please visit the Drizzlepac Jupyter Notebooks on GitHub.

Revision History





The DrizzlePac Handbook2.0February 2021

Hoffmann, S. L., Mack, J., Avila, R. J., Martlin, C., Bajaj, V., and Cohen, Y.

Susan Rose-Technical Editor

The DrizzlePac Handbook1.0June 2012

Gonzaga, S., Hack W., Fruchter, A., and Mack, J. et al.

Susan Rose-Technical Editor

The AstroDrizzle Mini-handbook1.0February 2012

Gonzaga, S., Hack W., Fruchter, A., Lindsay, K., Dencheva, N., Sosey, M.

Susan Rose-Technical Editor

The MultiDrizzle Handbook1.0November 2008

Fruchter, A., Sosey, M., Hack, W., Dressel, L., Koekemoer, A. M., Mack, J., Mutchler, M. and Pirzkal, N.

Susan Rose-Technical Editor

HST Dither Handbook2.0January 2002

Koekemoer, A. M., Gonzaga, S., Fruchter, A., Biretta, J., Casertano, S., Hsu, J.-C., Lallo, M., Mutchler, M. and Hook, W.

Susan Rose-Technical Editor

HST Dither Handbook1.0December 2000Koekemoer, Anton M., et al.


Drizzle documentation is the result of combined work by many individuals over the years. For this latest handbook version, primary contributors (in alphabetical order) are Amber Armstrong, Roberto Avila, Varun Bajaj, Mihai Cara, Yotam Cohen, Nadia Dencheva, Tyler Desjardins, Michael Dulude, Andy Fruchter, Shireen Gonzaga, Warren Hack, Samantha Hoffmann, Kevin Lindsay, Ray Lucas, Jennifer Mack, John Mackenty, Catherine Martlin, Larry Petro, Vera Kozhurina-Platais, Abhijit Rajan, Linda Smith, Chris Sontag, and Leonardo Ubeda.


In publications, refer to this document as:

  • Hoffmann, S. L., Mack, J., et al., 2021, “The DrizzlePac Handbook”, Version 2.0, (Baltimore: STScI).

For the design of AstroDrizzle and the enhancements to the FITS format it has introduced, please reference:

  • A.S. Fruchter, W. Hack, N. Dencheva, M. Droettboom, P. Greenfield, 2010, "BetaDrizzle: A Redesign of the MultiDrizzle Package" in STSCI Calibration Workshop Proceedings, Baltimore, MD, 21-23 July 2010, eds. Susana Deustua & Cristina Oliveira, Space Telescope Science Institute, pp 376 - 381. 


Information in this manual represents the cumulative experience and contributions of many members of the STScI community, including the WFPC2, WFC3, ACS, NICMOS and STIS instrument groups, the Observatory Support Group and the Science Software Branch.

The Drizzle code, which is at the core of MultiDrizzle and AstroDrizzle software, was originally developed by Richard Hook and Andrew Fruchter. It was subsequently implemented in the pipeline as MultiDrizzle, in an effort led by Anton Koekemoer. AstroDrizzle, which is written primarily in C and Python, replaces MultiDrizzle in the HST pipeline. Software development was led by Andrew Fruchter and Warren Hack, with contributions from Erik Bray, Mihai Cara, Nadia Dencheva, Michael Droettboom, Richard Hook (ESO), Chris Sontag, and Megan Sosey.

Under the leadership of ACS and WFC3 team leads at the time, Linda Smith and John Mackenty, respectively, the software was tested by Amber Armstrong, Roberto Avila, Howard Bushouse, Michael Dulude, Shireen Gonzaga, Ray Lucas, Jennifer Mack, Max Mutchler, Larry Petro, Norbert Pirzkal, Abhijith Rajan, and Leonardo Ubeda. We thank Sylvia Baggett, Matthew Bourque, Stefano Casertano, Matt Lallo, Janice Lee, Knox Long, Josh Sokol, and Brad Whitmore for valuable feedback on the software.

Susan Rose provided the technical expertise for publication of this document.