The Tiny Tim Page

The Tiny Tim Page

Download Tiny Tim

Tiny Tim version 7.0, which includes support for WFC3 and was developed at the ST-ECF, was released on June 1, 2008. A few minor fixes were made in version 7.1, released in December 2010. Go to the download page to get the command-line version of the software. Version 7.1 can also be executed through a new web interface.


The most recent Tiny Tim manual is available here. It is a must-read for anyone modelling the ACS. It was written for version 6.3 of Tiny Tim, but nothing changed in version 7.0 other than the addition of WFC3 instrument support. WFC3 ISR 2008-14 describes how WFC3 support was added to version 7.0

About Tiny Tim

Tiny Tim is a program that generates simulated Hubble Space Telescope point spread functions (PSFs). It is written in C and distributed as source code and runs on a wide variety of UNIX and VMS systems. Tiny Tim was written by John Krist. Early NICMOS support was provided by Richard Hook (ST-ECF/ESO). The WFC3 support was added by Richard Hook and Felix Stoehr (ST-ECF/ESO).

Tiny Tim includes mirror zonal errors, time dependent aberrations (for the pre-repair instruments), field dependent obscuration patterns (for WF/PC-1 and WFPC2), and filter passband effects. It can produce a normally sampled or subsampled PSF. Output is a FITS image file.

Some examples of the use of Tiny Tim model PSFs are given below, along with some links to related on-line documents. As one can see, most of my projects deal with WFPC2.

Frequently Asked Questions

Subtracting unsaturated WFPC2 PSFs
Convolving models with model PSFs
Deconvolving WFPC2 images
Also check out XZ Tauri for an example of subtracting models from saturated WFPC2 PSFs

For an overview of the difficulties dealing with the field dependence and large angle scattering in WFPC2, take a look at my conference proceeding "WFPC2 Ghosts, Scatter, and PSF Field Dependence" from the "Calibrating Hubble Space Telescope: Post Servicing Mission" Workshop, May 15 - 17, 1995. 5.5MB Postscript file.

The WFPC2 Calibration group at STScI also has a WFPC2 PSF Subtraction Page.

This page by John Krist with WFC3 additions from Richard Hook (July 2008)