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The main changes from a user perspective were as follows.
- Updated and expanded documentation, featuring the new recipes
and instrument-data supported, more on the ``Features of
the Primitives'', and a new appendix
listing the file prefixes.
- Added support for Magellan Classic Cam imager, and the ESO
NACO instrument in imaging mode. These have only processed
a few nights data exercising a few recipes. The NACO pipeline
would certainly benefit from more data.
- Upgraded support for the Gemini NIRI instrument from
pre-alpha to alpha, through more-thorough header translations,
adjusting the nominal WCS to an actual one, setting the saturation
levels, tested aperture photometry within a 3-arcsec aperture
of thermal data. It's still a work in progress, but it should be
possible to process non-thermal data too given a sequence of frames
matching a standard sequence.
- Incorporated eStar (intelligent-agent) calls in
in five recipes, including the two new recipes which make an
inventory of the sources such as
BRIGHT_POINT_SOURCE_CATALOGUE.
- The IRIS2 ARRAY_TESTS has been improved. The mode, speed,
and readnoise are written to the calibration log and reported.
- Several recipes in the BRIGHT_POINT_SOURCE
JITTER_SELF_FLAT families
and CHOP_SKY_JITTER
have two additional steps: one to correct for residual bias
variations along columns, and the other to correct for field
distortion. For most instruments these are null, but not for
ISAAC, where both are applied; and NACO, where the bias striping is
removed.
- The ISAAC sky co-ordinate system is tied to the undistorted
grid co-ordinates rather than than the distorted grid. This means
that measured sky positions for sources will not be misplaced by the
distortion. IRIS2 now corrects its world co-ordinate system for
spatial distortion, but the pixel grid is not resampled.
- Improved central-source registration and corrected the world
co-ordinate system associated with polarimetry products. The latter
includes allowance for the bifurcation in the Wollaston prism, and
the left-handed sky co-ordinates of UIST (by flipping the raw data
and WCS headers). Enlarged the extracted target and sky regions
for UIST.
- Combining sources in NOD_CHOP recipes revamped, using the
chop and nod offsets to decide upon the visibility of an image.
Thus it can now cope with just one positive-negative image pair.
- Centroid hunting allows for the source to be just outside
the initial search box, and should lead to better registration
of single sources and photometry, when the source is not placed
at the nominal location (such as shifted instrument apertures at
UKIRT).
- The option to clean small blemishes using a 15 x 15 box
filter during flat creation is now accessible from recipes, say when
invoking _FLAT_FIELD_MASKED_GROUP_.
- Object masking reports the detection threshold read from the
EXTRACTOR parameter file rather than a hardwired value.
- For ESO data CHOP_SKY_JITTER
allows the last frame to be of the target. Fixed a bug where the
normalised sky frames were flat-fielded prior to object masking
instead of flattening the frames with masked deviant pixels.
- Fixed a bug in determining a consistent set of sky levels for
CHOP_SKY_JITTER in multiple recipe
iterations.
- Fixed a bug where exposure time was not integrated in the
grand mosaic of EXTENDED recipes. The the start and end times and
airmasses are also updated in the grand mosaic's headers. The
mosaic's WCS is set to the SKY by default.
- Allow polarimetry recipes to work with angles of 0, 45, 90,
and 135 degrees. This permits the circular polarisation to be
determined from the Stokes images. Appropriately named flats for
90 and 135 degrees are created where necessary.
- There is a new polrefang calibration to correct the measured
polarisation angles to position angle, allowing for instrumental
alignment. The index file may be created manually to overide the
default calibrations.
- The default near-infrared polarisation selection criteria
have changed. The maximum polarisation threshold is increased from
50% to 75%. The standard deviation is relaxed to 10%. There is
a new criterion where the minimum intensity must be at least three
standard deviations above zero. The binning size is increased from
3 to 5 and its value is reported.
- The polarimetry-parameter images now have their world
co-ordinates set to SKY, so plots will be annotated with equatorial
co-ordinates.
- More intermediate frames are tidied at the end of recipes,
notably in CHOP_SKY_JITTER.
- Improved header translations for ISAAC, such as offering
fallback translations if the primary keyword is absent, setting
cumulative offsets to zero for the first jitter position,
recognising different observation-type values, and improved the
test for the source to be a standard for ESO data. More headers
are tested for a waveplate angle leading to greater robustness when
the polarimetry recipes are released. These improvements were based
upon experience of more data from a longer range of epochs.
- ORACUT now set for selection of calibrations of INGRID and ESO
data. Michelle's ORACTIME is now in decimal UT days.
- The changed Michelle headers are supported.
- Michelle reductions adapted to handle the nod iterator used
in observation preparation.
- UIST uses separate flat calibrations for imaging and
spectroscopy.
- The KAPVIEW display recognises a boolean key keyword.
If set to true (1), it places a key, such as the colour
table, besides the graphic.
The main changes from a programmer perspective were as follows.
- Much of the ISAAC code applies generally to ESO instruments.
There are new ESO/ directories for recipes and primitives. These
directories are ahead of the instrument-specific directories in the
search path for the recipe and primitive source code. ORAC::Frame::ESO and ORAC::Group::ESO modules from which
instrument-specific frame and group methods are sub-classed.
- Sigma-clipping is allowed for certain combination methods
during mosaic formation via a new SIGMA argument. There is also
a new ZERO argument to permit optional zero-point shifts between
contributing frames. While the default continues to apply intensity
offsets, Fabry-Perot wavelength mosaics set ZERO to false.
- There is a new POLARIMETRY argument for some of the
registration primitives.
- In aperture photometry primitives the centroid search
boxsize is now decoupled from the aperture size via a BOXSIZE
argument.
- LAMP is a new value for internal header
ORAC_OBSERVATION_TYPE to support internal lamps used to make
flats.
- The handling of the filters and standards' catalogues has
been redesigned in the photometry primitives to be be more
transparent and to make it easier to use multiple catalogues of
standards. A waveband is interchanged rather than a column index.
- _CALC_STOKES_ has a boolean DEBIAS argument to control the
application of the statistical-bias correction.
- _CALC_STOKES_NOD_CHOP_ has a new boolean CENTROID
argument, whose valued is passed to _COMBINE_CHOPPED_SOURCE_.
Next: Release Notes V4.0
Up: Release Notes V4.1
Previous: Modified recipes
ORAC-DR -- imaging data reduction
Starlink User Note 232
Malcolm J. Currie
Brad Cavanagh
Joint Astronomy Centre, Hilo, Hawaii
2004 June
E-mail:ussc@star.rl.ac.uk
Copyright © 2004 Particle Physics and Astronomy Research Council