CALSTIS 2.23 has not been installed in STSDAS yet, but will be distributed
with the release of STSDAS V3.6, which is anticipated to occur in late
November 2006. The OTFR pipeline currently uses CALSTIS 2.22 which was
installed in OPUS on 2006-Jul-12. When used in OTFR the differences between
2.22 and 2.23 only affect some diagnostic outputs, and do not change any
keywords or calibrated data values.
The following OPRs were implemented in the release of CALSTIS 2.22 and 2.23:
CALSTIS 2.22| OPR 56079: | Include a zero-point offset for CALSTIS blaze shift correction |
| OPR 56708: | CALSTIS7 should check for a WX2DCORR keyword switch |
| OPR 56746: | Verbose setting in CALSTIS6 when sc2dcorr is perform |
| OPR 56747: | xoffset for CALSTIS6 when sc2dcorr = perform |
These OPRs are discussed in more detail below.
OPR 56079: Include a zero-point offset for CALSTIS blaze shift correction
This change includes a zero-point offset for CALSTIS blaze shift correction.
Calstis was changed to read a new column, BSHIFT_OFFSET, from the PHOTTAB file.
This value is then used to adjust the zero point from which the Echeele blaze
shift is calculated. Previously, the calstis code calculated the blaze shift
in pixels as follows:
blaze shift = a*dx + b*dy + c*dt
The code now performs the following calculation instead:
blaze shift = a*dx + b*dy + c*dt + d
where the a, b, and c coefficients are pre-existing columns from the PHT
table and d is the zero point from a new column in the PHT table.
OPR 56708: CALSTIS7 should check for a WX2DCORR keyword switch
The new task 'wx2d' resamples a STIS image in the cross-dispersion
direction using wavelet methods. This task does not rectify the image
in the dispersion direction, and it does not perform flux calibration.
These can be done by the 'x2d' task (calstis7) on the output of 'wx2d',
but calstis first needed to be modified to recognize that wx2d had
already been performed. This OPR added the needed WX2DCORR keyword
calibration switch to calstis. This change to the X2D task allows it to
recognize and process output from the wx2d task, producing rectified and
flux calibrated output images equivalent to the default X2D output, but
with the wx2d wavelet interpolation in place of the usual bi-linear
interpolation used by X2D. As the WX2D task is not used as part of the
OTFR calibration, this change to the X2D code has no effect on the OTFR
calibrated output.
OPR 56746: Verbose setting in CALSTIS6 when SC2DCORR is perform
When x1d (calstis6) is run with sc2dcorr = perform (correct for Echelle
scattered light), it goes through several iterations, and it is only on
the final iteration that flux calibration and some other steps are done.
Previously, some messages that could be printed to the standard output
were not printed until the final iteration. The printed output during
the final iteration was nearly but not exactly the same as the printed
output when sc2dcorr is set to omit; in particular, most of the information
about the global cross correlation offset was not printed when sc2dcorr was
set to perform. This OPR changed calstis to print this information whenever
the 'verbose' parameter is set to yes.
OPR 56747: XOFFSET for CALSTIS6 when SC2DCORR = perform
Previously, when x1d (calstis6) was run with the echelle scattered light
correction (sc2dcorr) set to perform, it printed this message:
"Offset of -1 low-res pixels added in dispersion direction"
regardless of the value to which xoffset was actually set.
Calstis was changed to no longer produce this spurious message.
This did not have any effect on the data.