STSDAS v2.2 RELEASE SUMMARY The primary changes incorporated in this release are: 1) An updated DITHER package which includes many new and updated tasks to make it easier to use with other instruments and give better results. 2) An updated NICMOS package which includes some new tasks and many improved versions of recently added tasks. 3) New tasks to splice spectra (HST_CALIB.CTOOLS/SPLICE, FWEIGHT, SFLUX, and PWEIGHT). 4) A new version of CALSTIS (v2.7) which includes a number of changes to processing algorithms and bug fixes. 5) New and updated SYNPHOT tasks. 6) The task NEWREDSHIFT was moved to TOOLBOX.TOOLS from SOBSOLETE at a user's request. 7) Updates to the CVOS and HSTIO libraries. The following task has been moved from analysis.dither to sobsolete: analysis.dither -> sobsolete.oldither Packages or tasks that have seen significant changes include: analysis.dither hst_calib.nicmos hst_calib.paperprod hst_calib.stis.calstis Packages or tasks that have had minor enhancements or bug fixes include: analysis.fitting .gasp.stgindx .xyeq .isophote.bmodel .isomap .ellipse contrib.gaussfit .spfitpkg.specfit graphics.sdisplay.compass .stplot.igi hst_calib.ctools.ckwstis .mkmultispec .resample .tomultispec .fos.bspec .yfluxcal .stis.inttag .mkfringeflat .normspflat .ocrreject .prepspec .tastis .wavecal .x1d .synphot.bandpar .obsmode .plspec .pltrans .wfpc.uchcoord .warmpix playpen.hsubtract toolbox.headers.upreffile .imgtools.addmasks .boxinterp .gcopy .imcalc .mstools.msarith .mscombine .mscopy Parameter files that have changed (new parameters or new default values excluding changes to version or related parameters, or changes to parameter comments): analysis.isophote/magpar.par - 'refer' default changed graphics.sdisplay/compass.par - 'angle' default changed hst_calib.ctools/ckwstis2.par - added 'wcptab' /ckwstis4.par - added 'wcptab' hst_calib.paperprod/upp_image - added 'page' /xpp_image - added 'page' /upp_obsum - added 'page' /xpp_obsum - added 'page' hst_calib.stis/tastis.par - 'input' default changed - added 'acq_success' hst_calib.synphot/refdata.par - 'grtbl' and 'cmptbl' default changed hst_calib.wfpc/t_metric.par - 'cursor' changed