HST Focus Documentation:

FAQs:
Frequently Asked Questions.

Performance Summaries & Status Reports:

HST Secondary Mirror Moves
Table of HST Secondary Mirror Moves.
R. B. Makidon 25 Jun 2002

HST Thermal Focus Variations
HST Thermal Focus Variations.
J. Hershey 25 Jun 2002

HST Focus History
HST Focus History
TEL 25 Jun 2002

OTA Focus Review Memo
Focus history, mirror moves, and typical accuracy are reviewed.
M. Lallo 25 Jun 2002 (pdf)

Handbooks:

Telescope Image Modeling (Tiny Tim) Handbook
User's manual for "Tiny Tim". Software package for simulating HST PSFs. J. Krist 01 Jun 2004 (pdf)

Instrument Science Reports:

ISR-TEL-2006-01, Modeling Aberrations in the Advanced Camera for Surveys
Investigates the plausibility of optical misalignments as the cause of apparent aberration changes implied by phase retrieval of HRC PSFs
K. Houairi et al. 13 Oct 2006 (pdf)

ISR-TEL-2005-03, HST Temporal Optical Behavior & Current Focus Status
Reviews the timescales, mechanisms, and importance of variations in aberrations (focus, coma, astigmatism). Presents focus status of the observatory.
M. Lallo et al. 27 Oct 2005 (pdf)

ACS field-dependent PSF variations...
Examines PSF width and ellipticity variations over WFC and HRC field resulting from optical and charge diffusion effects.
J. Krist 03 May 2006 (pdf)

HST Focus in Year 2000 - A Review of the Cycle 9 Focus Monitor Program
OTA-2001-01: After the last HST refocusing in June 2000,an enhanced OTA focus monitor(8829) began running as a cycle 9 observatory-level calibration to supplement...
M. Lallo 21 Jun 2002 (pdf)

Modelling HST Focal-Length Variations
Paper on the Modelling HST Focal-Length Variations.
J. Hershey 25 Jun 2002 (pdf)

Focus Monitoring and Recommendation for Secondary Mirror Move
OTA-18: Focus monitoring and recommendation for secondary mirror move.
S. Casertano 20 Jun 2002 (pdf)

Papers and Proceedings:
Selected published papers and workshop proceedings.

Temporal Optical Behavior of HST: Impact on Science Observations
R. B. Makidon et al., May 2006

Temporal Optical Behavior of HST: Focus, Coma & Astigmatism History
M. Lallo et al., May 2006

HST Temporal Optical Behavior: Models & Measurements with ACS
R. B. Makidon et al., 30 Oct 2005

On-orbit alignment & imaging performance of HST ACS
G. F. Hartig et al. Jan 2002

Phase-retrieval analysis of pre- and post-repair HST images
J. Krist & C. Burrows, 1 Aug 1995