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Following the failure of the "backup" side 2 electronics on the Advanced Camera
for Surveys (ACS) on 27 January 2007, the Hubble Heritage Team was asked to
conduct some new high-quality multiwavelength WFPC2 observations. Although the
WFPC2 has been in continuous service since being installed during Hubble
Servicing Mission 1 in 1993, it has only had limited use since the installation
of ACS during HST Servicing Mission 3B in 2002. The purpose of our observing
program was to quickly illustrate the current WFPC2 data quality, and produce
Heritage-quality color composite images.
Our WFPC2 observations of these planetary nebulae were conducted in February 2007,
with a comprehensive set of filters. See HST programs
11090 and
11093 for more observation details.
A secondary goal was to demonstrate the best practices for WFPC2 pointing and
drizzling, and provide some concrete A-to-Z examples to help guide ACS users
currently converting their science programs to WFPC2.
Since many ACS users converting to WFPC2 will be seeking to recover as much
resolution and field-of-view as possible, we recently designed a broader suite
of suggested WFPC2 dither and mosaic pointing patterns, and also some
"cookbooks" for reducing the resulting data. See:
http://www.stsci.edu/hst/wfpc2/analysis/wfpc2_patterns.html
http://www.stsci.edu/hst/wfpc2/analysis/WFPC2_drizzle.html
The datasets described here reflect the pointing and drizzling strategies
described above. In each case, the planetary nebula is positioned on one of the
four WFPC2 chips, and a sub-sampling dither box pattern was employed. The
resulting data was then drizzle-combined to a finer output scale, as described
below. These drizzled images therefore give a good indication of the data
quality that can currently be expected for reasonably deep multiwavelength
imaging with WFPC2.
This release includes 4 targets, He 2-47, IC 4593, NGC5307, NGC 5315 are described here.
A prior release of data for another PNe, NGC 2440 was made in February 2007.
Filenames follow the naming convention
h_ooooo_fffff_drz_ttt.fits
- ooooo - object
- fffff - filter
- ttt is the type: science (sci) or weight.
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