Documentation for WebbPSF¶
WebbPSF is a Python package that computes simulated point spread functions (PSFs) for NASA’s James Webb Space Telescope (JWST) and Nancy Grace Roman Space Telescope. WebbPSF transforms models of telescope and instrument optical state into PSFs, taking into account detector pixel scales, rotations, filter profiles, and point source spectra. It is rather a tool for transforming optical path difference (OPD) maps, created with observatory systems engineering models, into the resulting PSFs as observed with JWST’s or Roman’s instruments.

Sample PSFs for JWST’s instrument suite, all on the same angular scale and display stretch.¶

Sample PSFs for the filters in the Roman WFI.¶
Contributors: WebbPSF has been developed by Marshall Perrin, Marcio Meléndez, Shannon Osborne, Robel Geda, Brad Sappington, Charles-Philippe Lajoie, Joseph Long, Justin Otor, Jarron Leisenring, Neil Zimmerman, Keira Brooks, and Anand Sivaramakrishnan, with contributions from Alden Jurling, Lauren Chambers, Ewan Douglas, and others.
Getting Started with WebbPSF¶
See Using WebbPSF.
Quickstart Jupyter Notebook
This documentation is complemented by an Jupyter Notebook format quickstart tutorial. Downloading and running that notebook is a great way to get started using WebbPSF.
Getting Help
For help using or installing webbpsf, you can contact the STScI JWST Help Desk at jwsthelp.stsci.edu, category WebbPSF/JWST Telescope.
Contents¶
- Introduction
- Requirements & Installation
- Release Notes
- Using WebbPSF
- JWST Instrument Model Details
- JWST Using Wavefronts Measured On Orbit
- JWST Implementing Detector Effects in Simulations
- Matching PSF sims to in-flight JWST data
- Visualizing the JWST Optical Budget
- Plots of JWST Wavefronts Over Time
- Roman Instrument Model Details
- Using PSF Grids
- More Examples
- Overview of POPPY (Physical Optics Propagation in Python)
Advanced Usage¶
Appendices and Reference¶
How to cite WebbPSF
In addition to this documentation, WebbPSF is described in the following references. Users of WebbPSF are encouraged to cite one of these.
Perrin et al. 2014, “Updated point spread function simulations for JWST with WebbPSF”, Proc. SPIE. 9143,
Perrin et al. 2012, “Simulating point spread functions for the James Webb Space Telescope with WebbPSF”, Proc SPIE 8842, and
Perrin 2011,
Improved PSF Simulations for JWST: Methods, Algorithms, and Validation
, JWST Technical report JWST-STScI-002469.
In particular, the 2012 SPIE paper gives a broad overview, the 2014 SPIE paper presents comparisons to instrument cryotest data, and the Technical Report document describes in more detail the relevant optical physics, explains design decisions and motivation for WebbPSF’s architecture, and presents extensive validation tests demonstrating consistency between WebbPSF and other PSF simulation packages used throughout the JWST project.
Mailing List
If you would like to receive email announcements of future versions, please contact Marshall Perrin, or visit maillist.stsci.edu
to subscribe yourself to the “webbpsf-users@maillist.stsci.edu” list.