Observing Once Again with WFPC2...
For many years, the Wide Field Planetary Camera 2 (WFPC2) detector on the Hubble Space Telescope was the main workhorse of optical images and certainly "pretty pictures" being released by the Huble Heritage Project. In 2002, a newer, better camera was installed on Hubble, the Advanced Camera for Surveys (ACS), and we had a new stallion that could look deeper, with better resolution, and that did not have large sections of the field missing.
Size and shape differences between ACS and WFPC2
Following the recent electronics failure of the Advanced Camera
for Surveys in January 2007, the Hubble Heritage Team was asked to
conduct some new high-quality multiwavelength WFPC2 observations. The purpose of this was to
quickly illustrate the current WFPC2 data quality, and produce a
Heritage-quality color composite image.
A secondary goal was to demonstrate how astronomers, who were currently scheduled to use Hubble or were proposing to use it in the future, could convert ACS science programs to WFPC2. With a bit of preplanning ACS users are able to recover much of the
resolution lost in switching to WFPC2. The example below illustrates the improved resolution that is possible when WFPC2 observations are made with optimal sub-pixel dithering.
Normal resolution of WFPC2 data. (Place mouse over image to overlay enhanced resolution.)
Enhanced resolution of sub-pixel dithered WFPC2 data. Illustration Courtesy of M. Mutchler (STScI)
High-level Science Products for WFPC2 observations of NGC 2440 as well as a document on how to refine the WFPC2 resolution with sub-pixel dithering and combining is available from the Hubble archive.