CHANGES TO APPLICATIONS ANALYSIS.DITHER - PYDRIZZLE PyDrizzle has been updated to Version 4.4 for this release. This version has been updated to incorporate rigorous WCS fitting algorithms to accurately handle shift and rotation determinations for all declinations. The new algorithms improve the accuracy of the registration for images taken with the same HST guide stars to less than 0.1 pixel. Also, support for new shiftfiles provides the user with the ability to update the shifts computed from the header WCS information. Thus, even for observations taken using different guide stars and orientations, use of the shiftfiles with PyDrizzle can result in registrations better than 0.1 pixel. In addition, new Python methods have been added to simplify processing by PyDrizzle allowing the user to change the parameters for the output product without starting over. The 'resetPars' method accepts a new SkyField object as the new description of the output field and recomputes the drizzle parameters based on that description. A 'clean' method was also added to assist in removal of intermediate files when processing needs to be restarted. The output of the parlist object was also made more human-readable when printed out with the Python 'print' command while using Python syntax for running PyDrizzle. PyDrizzle was also modified to produce GEIS products as the direct output from 'drizzle' avoiding problems encountered with the IRAF FITS kernel, and also speeding up output of the drizzle products. The new 'readgeis' module based on PyFITS has been used to convert those GEIS outputs into FITS output for the user. Revisions were made to support the newer IDCTAB format for ACS data. This new format for the distortion coefficients table supports separate distortion models for each filter combination. Application of the new 'VAFACTOR' keyword in ACS images to correct for velocity aberration was also implemented in this version of PyDrizzle. A number of changes were made to improve support for processing WFPC2 data. Support for processing only a single chip of a multi-chip image was implemented using the 'section' parameter. All uses of the keypar task were removed to prevent different processes from interferring with each other by updating the output parameter for the keypar task. Fixed a problem with a module attribute (EXTLIST) causing reuse of the previous value for the next run within the same session For more details on specific changes made to all versions of PyDrizzle, please review the 'History' file in 'stsdas$python/pydrizzle'. - BLOT Blot was updated to v2.02. The main changes are new interpolation kernels, including "sinc" and better handling of large input images. - BUILDASN This task was updated to work with the new format of shiftfile. This supports generation of ASN tables for WFPC2 datasets which have externally updated shifts, such as those provided by CADC for the 'B'-type associations. In addition, bugs were fixed to now properly read WFPC2 .c1h files and build a full static mask for use by 'drizzle'. - DITHER Drizzle was updated to v2.92. Main changes are the inclusion of a "Lanczos" kernel options that can produce output images with better resolution and reduced correlated noise, at the expense of longer running time. Other minor changes are improved file and memory management for very large output images. - GENERAL The IRAF interface code was modified to use a single IRAF variable to point to the PyDrizzle code location: mdrizzle. This simplified installations for those setting up personal versions of this code when updating the system version is not possible or desired. Support for the new 'lanczos3' kernel was also added to the IRAF interface. This new kernel, though, requires drizzle Version 2.9 (as distributed with this release). - TRAXY Traxy was updated to v1.4. Main changes are use of the same geometric transformation code as other dither tasks and the addition of the "silent" parameter. - TRANBACK Updated to v1.3. Uses same code as other tasks for geometric transformations. - WCS2DR (new task) This task takes the World Coordinate System (WCS) keywords from image headers, along with the applicable geometric distortion coefficients and deduces the drizzle parameters needed to be used to register one image with another. ANALYSIS.ISOPHOTE - ELLIPSE The help file was modified to give a more accurate explanation of higher order harmonic amplitudes. ANALYSIS.STATISTICS - EMMETHOD The help for 'emmethod' has been modified to say that censor indicator 5 (which implies a dependent variable that is confined between two values) should not be used. The code (from the ASURV package from Penn State) includes this option, but it does not work. HST_CALIB.ACS - CALACS CALACS Version 4.3a implements primarily bug fixes and minor additions to information reported in the image headers. New BIASLEV keywords were added to ACS image headers to report the bias levels computed by CALACS from the overscan regions for each amp used to take the image. These keywords were added to ACS image headers starting the week of 9-June-2003. A bug was fixed in ACSCCD to use the correct default ccdbias values from the CCDTAB for chip 2 of WFC observations. This corrects problems seen in the ERR array as well as the bias level subtraction for subarrays that do not extend into the overscan regions on WFC chip 2. ACSREJ was also modified to correctly handle associations where some or even all the input exposures have an EXPTIME of 0. This fix included revising how the keyword REJ_RATE was computed to more accurately reflect the datasets. Also, changed how SCALENSE was used in computing threshhold values for detecting cosmic rays, especially in SPILL pixels. High values of SCALENSE previously resulted in halos around cosmic-ray cleaned pixels. John Blakeslee also modified 'acsrej_init' to apply the same criteria when creating the initial guess image. Corrected problems with processing RPT-OBS associations, such as directly using output names from ASN table for output product so that PyDrizzle can find the proper file to correct. Dither combining step now captures STDERR messages from the CALACS and PyDrizzle steps and adds them to the trailer file. Added completion timestamps to trailer file. Other minor improvements to trailer file entries were also made. Warning messages about unavailable graphics displays have been suppressed at the request of operations. The wrong bias values were being used from CCDTAB for WFC chip 2 data. This has been corrected. HST_CALIB.CTOOLS - CKWSTIS3 A 'tdctab' parameter was added. - CKWSTIS4 'tdstab' and 'tdctab' parameters were added. HST_CALIB.NICMOS - CALNICA A bug that caused the ZSIGCORR step to crash on Tru64 systems with certain data sets was fixed. - CALNICB Changed to accept any pattern type, even those defined for other HST instruments (in particular "LINE" and "SPIRAL"). - MOSDISPLAY Modified to make local copies of all parameter values in order to avoid repetitive prompting for parameter values. A bug was also fixed in the parameter specifications, which was causing the task to always prompt for hidden parameter values when running from PyRAF. - SAMPCUM, SAMPDIFF Upgraded to automatically load all necessary packages for tasks called by these scripts. HST_CALIB.PAPERPROD Modifications were made for STIS to work properly with JIF files and changes were made to the CL scripts so that they work properly with PyRAF. The version is now 2.33 HST_CALIB.STIS - CALSTIS A correction for charge transfer inefficiency for CCD data is now included in the flux correction step for 1-D spectral extraction. The error estimate in 1-D extracted CCD data now includes a correction to handle the case that more than one electron may be generated from a single UV photon. The input file for 1-D spectral extraction is an image and has keywords for describing the transformation between pixel coordinates and "world" coordinates (wavelength and angle along the slit). These keywords are no longer copied to the output file, because that file contains a table rather than an image. A change in a previous release of CALSTIS resulted in a problem with DOPPCORR for FUV data. The exposure start time was not being read from the header but was left with the default value of zero. The convolution of reference files with the Doppler shift during the exposure would therefore be out of phase. This has been fixed. The scale noise parameter for cosmic ray rejection is part of the noise model, intended to prevent rejection of the cores of point sources when the individual CR-split exposures are not perfectly aligned. It was inappropriately being applied to pixel values that include the sky background. It is now applied to sky-subtracted pixel values. Part of wavecal processing is to determine the shift of the image in the cross dispersion direction. This is based on a cross correlation which results in a roughly triangular peak. The algorithm for finding the location of the peak has been improved. A bug in the memory allocation - deallocation management code was fixed. Memory used for spectrum trace information was not being properly freed. This caused a segmentation violation when running the scattered light correction algorithm. The bug surfaced only when the first spectral order in the image fell off the detector. A memory initialization bug that caused random crashes was fixed. Crashes would be in the form of floating point errors under Linux, or high performance trap errors under Tru64. Under Solaris the bug did not surface, probably because Solaris C libraries initialize memory in a different way than Linux and Tru64. The bug was associated with the blaze shift correction and happened only with first order data. The file 'gettds.c' in the CALSTIS support library did not link correctly under HP-UX because of a CVOS-style function whose name ended with a underscore. The fix consisted in adding the 'if NO_UNDERSCORE' construct to the source code, and adding an include statement for c_iraf_priv.h CALSTIS was failing when no grating entry was found on the TDSTAB reference file; it now just skips the TDS correction. A bug that caused an arithmetic trap exception was fixed. The variable used for reading the optional list of scaling factors for the dark reference image was not initialized. This might normally be harmless, but it could result in the dark reference image being scaled by an arbitrary factor. - DOPPINFO (new task) This is a new task that prints information about the Doppler shift during a STIS observation. - INTTAG The FITS standard now specifies different keywords for images and tables for mapping between pixel coordinates and "world" coordinates (such as right ascension and declination), and it prohibits the presence of image-type keywords in a table header or table-type keywords in an image header. inttag was modified to conform to this standard. - ODELAYTIME This task was originally written for time-tag data; it modifies the times of the events as well as the header keywords for the exposure start and stop times. It was modified so that it can also be run on 1-D extracted spectra or image sets, in which case the task only updates the header keywords. Another change was to allow the 'obs_ephem' parameter to include more than one ORB table, to handle the case where the exposure started during the interval covered by one ORB table but ended in the interval for another one, or to handle the case that multiple input files were specified. The times for 'earth_ephem' and 'obs_ephem' are now read from columns in those tables, rather than being computed from header keywords. - STISNOISE (new task) (requires PyRAF) This task removes fixed pattern noise from STIS images. It computes an FFT on STIS CCD frames to evaluate fixed pattern noise. Fixed pattern noise is most obvious in a FFT of bias frames from side the B electronics. Optional filtering to correct the fixed pattern noise is provided through keywords 'boxcar', 'wipe', and 'window'. The 'freq', 'ampl', and 'fwhm' parameters return information about the maximum peak in the FFT and can be used for filter the data. Filtered data can be saved as an output file. - TASTIS An 'update' parameter was added. If this is set to yes, several keywords will be added to the primary header of the input file(s) to record the success or failure of various tests. The visit "number" can include a letter, but a numerical buffer was used to hold the value; a string buffer is now used. The limits in many of the tests have been modified, and some new tests have been added. Many of the messages (both warning and success messages) have been revised to make them clearer. HST_CALIB.SYNPHOT Changes were made to the computed wavelength limits for the output spectrum. Specifically, only the upper limit is increased when redshifts are involved so that the input source spectrum is not truncated at its lower end with the redshifted lower end before it is redshifted. Previously incorrect spectra were computed for redshifted spectra because the source flux was truncated to the final lower wavelength limit before being redshifted (rather than after). - MODEINFO (new task) This is a new task in the Synphot package, which can be used to list all known observation mode keywords for a particular HST instrument or filter system. Information about the use and application of each keyword is also presented. See the on-line help page for more information. - GRAFPATH Fixed a bug that prevented the task working properly when thermback changes were implemented (calling sequence to searchgraf had been changed). - THERMBACK The help file for the task was omitted in the last release and is now included. HST_CALIB.WFPC All tasks have been modified to work with FITS files in the appropriate format (they continue to work with the traditional GEIS format as well). Note that this is not the FITS files that are currently obtained from the HST archive, but rather FITS files that place each GEIS group in a separate image extension with the group parameters as header keywords in that extension. This work was done to facilitiate using CALWP2 and its associated tasks with a machine independent format. HST operation pipelines now process all WFPC data in FITS format. Utilities are available from STScI to convert WFPC2 GEIS files to and from this FITS representation. Type "help wfpc option=sysdoc" for more information. - CALWP2 Will search for reference files specified in the header in either format. If the header specifies a GEIS file and it is not found, CALWP2 will look for a FITS file with the same rootname. Likewise, if a FITS file is not found, the correspondingly named GEIS file is looked for. This allows CALWP2 to work with datasets and reference files converted to FITS even though the headers still refer to GEIS files. - COMBINE DATAMIN and DATAMAX now properly updated. - UCHCOORD Fixed an inconsistency between uchcoord and the Archive. The task uchcoord now works properly for OTFR WFPC2 files by checking the header keyword PROCTIME instead of PROCDATE. - ENGEXPR Fixed a bug in the task engexpr to produce consistent results (initialization problem). - CHECKWFPC Fixed a bug in the task checkwfpc to work properly for both WF/PC and WFPC2. TOOLBOX.HEADERS - IMINFO The task was updated to handel ACS, COS, and WFC3. TOOLBOX.IMGTOOLS - ADDMASKS The function that creates a new mask now can determine the type of the new mask (image, pixel list image, or table) from the filename extension of the output file. - IMCALC The help for 'imcalc' has been modified to describe the difficulty in testing for invalid operations, such as divide by zero, and to give an example of a workaround. TOOLBOX.IMGTOOLS.MSTOOLS - MSCOMBINE It used to be necessary to set imtype to "hhh" in order to run mscombine, simply because the cl script used temporary file names that lacked the filename extension. An explicit ".hhh" is now included in the temporary strings for image names in mscombine.cl. When working with NICMOS images, the TIME and SAMP extensions have been swapped in the output so that the SAMP extension is now written before the TIME extension. TOOLBOX.TOOLS - TEPOCH (New Task) This task does time format conversions for table columns. CHANGES TO DATA FILES cosiaf.fits This file has been updated to use the 3/3/2003 version of the SIAF.