INSTALLATION (Nov10)             mscred             INSTALLATION (Nov10)



                  MSCRED: CCD MOSAIC REDUCTION PACKAGE
              Release Notes and Installation Instructions



SUMMARY
The  MSCRED  external package is used to reduce CCD mosaic data in which
the data is in the mosaic MEF data format.



RELEASE INFORMATION
The following summary only highlights the  major  changes.   There  will
also be minor changes and bug fixes.


V5.0:  November 17, 2010
    Many changes and updates to be documented shortly.

V4.9:  August 12, 2008
    Bug fix for mscwcs task.
    Bug fix for flipped data in CCDPROC.  The bug fix noted below for
    binned data was incomplete in that it introduced an error for
    flipped data.

V4.8:  Feb 13, 2006
    The  last bug fixes were April 15, 2005 but no release was made with
    those changes accumulated  since  the  last  release.   The  changes
    include  a  bug  fix  for a bad CCDSEC in binned data, support for a
    new feature in XImtool,  a  restructuring  of  how  the  package  is
    built,  a  bug  fix  for  PATFIT, addtion of an environment variable
    "imcombine_maxmemory" to allow control  of  memory  allocation,  and
    searching  for  bad pixel masks both in the current directory and in
    the directory in which the input  images  are  located  in  COMBINE.
    The   main   reason   for   this   distribution   is   provide   the  
    imcombine_maxmemory environment variable feature.
    
    imcombine_maxmemory (default = 250000000)
        This  task  tries  to  use  the  maximum  possible  memory   for 
        efficiency  when  dealing  with  lots of data and is designed to
        reduce memory usage if memory allocation fails.  However,  there
        may  be  cases  where  this  adjustment  fails  so this variable
        allows forcing the task to stay  within  a  smaller  allocation.
        This  variable  is  in  bytes  and  the  default  is  the amount
        generally returned by  the  system.   It  is  large  because  of
        virtual  memory  functionality.  If problems are encountered one
        should try setting  this  variable  to  a  smaller  size  until,
        hopefully, the out of memory errors disappear.

V4.8: May 11, 2004
    MSCCMATCH now allows any number of sources to be rejected by the bad
    pixel/saturation mask  during  the  fine  centroiding.   The  coarse
    search  works  as  before and ignores the mask if more than half the
    search regions have bad pixels flagged.  There is also  now  another
    output  log  line  giving  the average x/y shifts which is different
    than the tangent  point  shift  which  is  a  function  of  the  WCS
    solution.

V4.8: February 25, 2004
    MSCGETCATALOG now outputs an extra digit of precision.
    
    An error in MSCCMATCH about too many "ctran" descriptors was fixed.

V4.8: December 30, 2003
    MSCFOCUS/MSCSTARFOCUS  was  not  working  correctly  since the April
    version.
    
    XTALKCOR was modified to allow  mosaics  with  few  extensions  than
    given  in  the  coefficient  file provided that the extensions don't
    reference any missing extensions.
    
    MSCSHUTCOR was added  to  allow  measuring  shutter  corrections  in
    mosaic format data.

V4.8: November 6, 2003
    MSCCMATCH  was fixed to allow automatic outlier rejection by setting
    the "reject" parameter.  This function was not working  even  though
    the  parameter was present because a hidden parameter for the number
    of rejection iterations was not set.
    
    MSCSETWCS would not work on  database  files  produced  by  MSCTPEAK
    using non-MEF data.

V4.8: July 30, 2003
    A  bug  was  fixed  which  caused  a  memory  corrupted  error  when 
    combining  data  in  physical  coordinate  space  when  there  is  a 
    relative  flip  between  images.  This type of combining occurs when
    merging multiple amplifiers.  Note this only affects data where  the
    raw  storage order of multiple amplifiers is flipped.  Some systems,
    such as at NOAO, flip the data  to  a  standard  orientation  during
    readout.

V4.8: July 28, 2003
    This  fixes  a bug in CCDPROC when the data storage order is flipped
    with respect to the CCD pixels and the  TRIMSEC.   This  bug  causes
    the  LTV  keyword  to  be  off when applying the trimming operation.
    The LTV error affects merging amplifiers and other operations  based
    on the physical CCD coordinate system.

V4.8: June 24, 2003
    This fixes a bug in CCDPROC on Solaris when using the fixpix option.

V4.8: April 11, 2003
    This  fixes a bug affecting MSCZERO, MSCCMATCH, MSCCTRAN, MSCTVMARK,
    MSCPIXAREA, MSCGETCAT, and MSCIMAGE.  This bug was introduced in the
    March  releases.   It is reported in IRAF bug log #552.  There is no
    workaround and anyone who installed one of the March releases should
    upgrade.

V4.8: March 25, 2003
    PATFIT/RMFRINGE/RMPUPIL  had  a  bug  when using the block averaging
    with certain combinations of background levels.

V4.8: March 14, 2003
    PATFIT/RMFRINGE/RMPUPIL now have an  option  to  block  average  the
    input,  pattern, weight, and masks to reduce noise.  Note that there
    are new parameters in RMFRINGE.
    
    The merging of masks with the "merge" option in CCDPROC  had  a  bug
    when  the  masks  are  added  to  during CCDPROC.  This has now been
    fixed.

V4.8: November 4, 2002
    MSCCMATCH  has  additional  parameters  and   the   parameters   are 
    functionally  grouped  in  epar.   The  new  parameters  allow finer
    control of the centroiding  and  failure  conditions.   The  default
    values produce the same results as before.
    
    XTCOEFF  coefficients  were  biased  by not using an accurate victim
    background and not using  any  source  background.   A  new  version
    includes  parameters  for  the  backgrounds as well as for an object
    mask to be applied to the victim to exclude contaminating objects.
    
    COMBINE and related tasks were incorrectly reporting the  mask  file
    used  in  the logfile though the correct mask was being used for the
    combining.
    
    CCDPROC did not recognize setting the bleed trail value relative  to
    the saturation value.

V4.7: June 14, 2002
    Fixed  a bug in COMBINE (which is called by various other tasks such
    as ZEROCOMBINE, FLATCOMBINE,  and  MSCIMAGE)  which  could  cause  a
    segmentation violation.

V4.7: May 28, 2002
    This  version  has features that require IRAF V2.12.  In particular,
    use of nproto.objmasks to make object masks for  proper  fringe  and
    pupil  removal  and  support  for masks in FITS files.  However, the
    package will still work with V2.11.3 and with pl masks.   Note  that
    not all tasks, such as CCDPROC, have been updated to use FITS masks.
    
    Two  new  non-interactive  tasks,  RMFRINGE  and  RMPUPIL,  automate 
    removal of fringe and pupil patterns.   The  old  interactive  tasks
    have  been  renamed  to  IRMFRINGE  and  IRMPUPIL.   As part of this
    change the task MSCPUPIL has a new output type "mask" to  produce  a
    mask for identifying the pixels corresponding to the pupil pattern.
    
    MSCGETCATALOG  is  now  interfaced  with the V2.12 ASTCAT package to
    provide access to multiple on-line catalogs.

V4.6: December 7, 2001
    MKMSC is a new task for creating multiextension  format  files  from
    data  in  which multiple amplifier readouts are stored as regions in
    an image.  This allows CTIO ARCON QUAD and ESO VLT FORS1 formats  to
    be  converted  to allow MSCRED to be used to reduce the data.  There
    may be other formats for which this task might also be useful.

V4.6: December 4, 2001
    A bug was fixed in COMBINE when applying scale factors from  a  file
    or  keywords.  The values were improperly normalized.  This probably
    only affects Linux versions.

V4.6: November 26, 2001
    MSCCMATCH has been revised to detect  bad  coordinate  matches.   In
    particular,  when  the  fine  centroiding  is  done on all the input
    coordinates, it  will  detect  a  failure  to  centroid  on  a  real
    object.   Previously positions near the estimated positions would be
    found even when there  is  no  object  resulting  in  an  apparently
    reasonable  pattern  of  sources  for the coordinate correction.  If
    more than half of the candidate coordinates  fail  to  centroid  the
    matching  is  considered  to  have  failed and an error is reported.
    Other changes include being more robust when large search radii  are
    used.   Mainly  this  means that with large search areas around each
    candidate objects, where the probablility of  including  bad  pixels
    becomes  high,  the  bad pixel map is not used to exclude candidates
    in this search.  Note that bad pixels in the  fine  centroiding  box
    will  still  exclude  the object from consideration.  MSCCMATCH will
    also now work with single images as well as MEF mosaics.
    
    CCDPROC has been revised to add the  processing  parameter  "split".
    If  this  parameter  is  selected then the extensions are split into
    separate  images  during   processing.    This   is   intended   for 
    applications  where  the  CCDPROC  processed  images will be used in
    further analysis as individual  images.   Splitting  the  extensions
    during  processing  not  only  saves  a  later splitting step but is
    somewhat more efficient in execution.
    
    MSCDISPLAY has a new  feature  useful  for  generic  multi-extension
    data  or  for  sets of images that are tiled.  If there is no DETSEC
    keyword but there is a WCS then the display will be tiled using  the
    nearest  approximation  based  on the WCS.  Approximation means that
    nearest display pixel center is used but the images are not  rotated
    or resampled.

V4.5: May 4, 2001
    CCDPROC  has  a  new  option  to  identify  bleed trails.  The bleed
    trails may be marked in an output mask and/or removed from the  data
    by linear linear interpolation.
    
    CCDPROC  will now merge pixel masks when merging multiple amplifiers
    from the same CCD.  This is done only if the  resulting  pixel  mask
    is different.
    
    MSCCMATCH was enhanced to work with simple single images.

V4.4: March 6, 2001
    There   is  a  new  version  of  MSCIMAGE  which  handles  arbitrary 
    rotations,  creation  of  MEF  resampled  data,  and  parameters  to 
    explicitly  set a simple standard output coordinate system.  The new
    version has been carefully compared with the old version  and  gives
    identical  results down to the the roundoff error.  However, the old
    version may be excuted with the hidden task MSCOIMAGE.
    
    MSCZERO was updated again to correctly handle CFH12K data.

V4.3: February 23, 2001
    An error in creating the distribution file  mscred.tar  resulted  an
    older  version  of  the  sources  being  used but with new binaries.
    This distribution is the  correct  one  for  the  February  8,  2001
    release along with the following changes.
    
    MSCMEDIAN  is  a  new  task that allows running the IMAGES.MEDIAN or
    IMAGES.FMEDIAN tasks on the extensions of a mosaic  file.   It  also
    has  the  option  to output the difference between the input and the
    median filtered data.  Using this task with difference output  on  a
    sky  flat  created from data without fringing removed will produce a
    fringe frame for application with RMFRINGE.

V4.3: February 8, 2001
    A bug in the V4.2 version of CCDPROC which  could  potentially  lose
    data  in situations where the input to CCDPROC consists of a mixture
    of processed and unprocessed files is fixed (see  bug  log  479  for
    details).
    
    COMBINE  and  the  related  task  MSCSTACK  were modified to provide
    additional supplementary outputs.  Bad pixel mask are  specified  by
    the  new  parameter  "bpmasks",  where  mask values of 1 indicate no
    output data and  0  indicate  combined  data.   Exposure  masks  are
    specified  by  the  new  parameter "expmasks", where mask values are
    the sum of the input exposure  times.   The  headers  of  the  input
    images   may  be  saved  as  dataless  FITS  extensions  in  a  FITS 
    multiextension file specified by the new parameter  "headers".   The
    previously  available  output  mask  giving  the  number  of  pixels 
    rejection is now specified by the parameter "nrejmasks"  instead  of
    "plfile".
    
    The  output  header is a copy of the first input file in the list as
    before, but now the exposure time and dark time are not modified  by
    an  attempt  to give an effective exposure time.  Now the input data
    is scaled to the first input for combining rather than some  average
    value  as  previously  done.   This  means  that the keywords in the
    output  header,  such  as  exposure  time  and  airmass,   will   be 
    representative of the final data.
    
    The  output  header  will  contain  indexed  keywords  IMCMBnnn  and 
    PROCIDnn.   The  former  will  be  the  filenames  of   the   images 
    combined.   The  latter  will  occur  only when the data contain the
    keyword OBSID or PROCID and will be copies of the keywords from  the
    input  data.   PROCID is generated by CCDPROC and COMBINE from OBSID
    if present and thereafter PROCID is updated when the data  has  been
    modified by these and certain other reduction tasks.
    
    A  bug in COMBINE with the "grow" option that caused memory usage to
    increase until an out-of-memory or memory corruption error  occurred
    was   fixed.    This   would   typically   occur  with  the  variant 
    SFLATCOMBINE.
    
    A bug was fixed in MSCFINDGAIN where the specified  bad  pixel  mask
    was not actually used.

V4.2: January 30, 2001
    XTALKCOR  was  upgraded  from a script to a complied task.  This new
    version supports  multiple  amplifiers  affecting  the  same  victim
    extension.   It  also  adds the capability to create bad pixel masks
    of  the  affected  pixels.   The  parameter  file   has   additional 
    parameters.
    
    CCDPROC  was  modified  to use the new crosstalk correction routine.
    It functions in the same way as previously with no  new  parameters.
    The  application  to multiple amplifiers is transparently determined
    by the crosstalk correction file.
    
    CCDPROC was also modified to change  the  default  for  the  "merge"
    parameter  to yes.  This is a no-op for data where there is only one
    amplifier per CCD and is  the  correct  thing  to  do  for  multiple
    amplifier per CCD mosaic data.

V4.1: December 14, 2000
    The  "saturation"  parameter  in CCDPROC, which works in conjunction
    with "bpmasks", may now be  specified  with  the  following  syntax.
    The  first word is the desired saturation value.  It may be either a
    number (INDEF to not look for saturated pixels) or  a  keyword  name
    with  or  without a leading '!'.  The second word is the units which
    may either be "ADUs" or "electrons" with abbreviation  allowed.   If
    no  unit  is  specified  then  it  defaults to ADU.  If electrons is
    specified then the header must contain  the  "gain"  keyword.   Both
    the  saturation  keyword  and  the  gain  keyword  may be translated
    through the translation file.
    
    A minor enhancement of MSCZERO to work with  data  which  have  both
    flips and TRIMSEC.

V4.1: December 13, 2000
    This  version  fixes a memory usage problem with CCDPROC as reported
    in bug 476.

V4.1: December 7, 2000
    In   certain   circumstances   CCDPROC   could    apply    different  
    normalizations  to  each extension when flat fielding.  This release
    fixes this potential problem as described in bug enty 474.

V4.1: December 5, 2000
    MSCFINDGAIN was improved to allow use of bad pixel masks  and  sigma
    clipping.  The output format was also improved.
    
    MSCDISPLAY  and  MSCZERO had minor bugs dealing with extensions that
    are stored flipped relative to the way  they  should  be  displayed;
    i.e.  the  amplifier  readout  order  relative  to  the  CCD  is not
    corrected when recording the data.

V4.1: October 2, 2000
    CCDPROC was fixed to eliminate a query for an output bad pixel  mask
    when processing a dependent calibration image.
    
    MSCCMATCH  was  improved  during  the  automatic search.  Previously
    regions which partially fell outside  an  image  would  be  excluded
    without  replacement  by  another  region  leading  to possibly poor
    statistics and a failure to find the offsets.
    
    A potential problem was fixed where an explicit extension,  such  as
    image[1],  is  accidentally given instead of the root MEF name could
    lead to an infinite loop.

V4.1: September 20, 2000
    This is a minor bug fix release only.   The  only  significant  bugs
    were  in  MSCTPEAK.  So the only reason to update is if you use this
    task.
    
    The other bug to be aware of is that  using  "*"  in  the  "extname"
    parameter  of  various  tasks  may  cause  the  task  to  hang.  The
    extension  name  parameter  is  for  pattern  matching  rather  than 
    filename  matching  and  "*"  means  to  match  zero  or more of the
    preceeding character; so what should be used is "?*".   The  pattern
    matching  all  extensions  in  MSCRED  is "".  A bug fix was made to
    treat the special case of "*" in the way many  users  expect,  which
    is  to  match  all  extensions names in the same way as "" currently
    does.

V4.1: September 6, 2000
    MSCIMAGE was modified to better mask the  interpolated  edge  pixels
    and  to  provide  user  control  of the boundary extension.  The new
    parameters are "boundary" with a  default  value  of  "reflect"  and
    "constant"  with  a default value of 0.  The masking at the edges is
    now done differently by having the "ntrim" parameter  apply  to  the
    input  pieces  rather  than  the  projected  rectangle in the output
    sections.  Previously it was possible, because  of  the  distortions
    and  rotations  of  the  CCDs,  for the trimming to not exclude edge
    data uniformly thus requiring a much  larger  trim  than  is  really
    necessary.   Trimming the input is easier to comprehend and provides
    good control of interpolation  edge  effects.   The  help  page  was
    revised  to described the changes and better explain the use of this
    task.
    
    MSCIMAGE and MSCTPEAK will now work with single images  as  well  as
    multiextension  mosaic  exposures.   This  satisfies requests to use
    these tasks (along with MSCDISPLAY, MSCZERO, and a few other  tasks)
    for  non-mosaic  data.   These changes were made because it was easy
    to do.
    
    MSCEXAMINE  has  a  new  key,  't',  and  new  parameters  "output", 
    "ncoutput",  and  "nloutput".   This  key  outputs  a section of the
    displayed mosaic field centered on the cursor.  The output  name  is
    a   specified  rootname,  defaulting  to  the  name  of  the  mosaic 
    exposure, with a sequence number that is incremented  for  each  new
    output.   IMEXAMINE  will  include  this  feature  in  the next IRAF
    release.  Among the uses  of  this  feature  is  the  extraction  of
    wavefront  measurement  stars at the telescope using a mosaic as the
    detector.

V4.0: August 22, 2000
    This version includes the following major enhancements.
    
    MSCCMATCH can locate zeropoint  offsets  of  a  few  hundred  pixels
    along  with  small  rotations  of  order  a degree.  This is done by
    looking for position correlations among  the  brightest  sources  in
    the  coordinate  list.   The  "coarse  search"  is  enable  with new
    parameters.   If  a  significant  correlation  is  found  then   the 
    centroiding  of  all the input sources for the fine adjustments of a
    few pixels is done as before followed by the  fitting  of  a  global
    coordinate  system  correction  for  offset,  scale,  rotation,  and 
    atmospheric refraction.  For the fitting the rejection sigma is  now
    a  parameter.   Other new features include use of bad pixel masks to
    exclude sources with bad pixels, the ability  to  output  a  revised
    coordinate  list  of  just  those sources in the field which have no
    bad pixels and were not removed during centroiding, and the  ability
    to  execute a task to get a coordinate list of sources for the input
    exposures.  The last feature is very useful in conjunction with  the
    new   task  MSCGETCATALOG  noted  below.   The  new  parameters  are 
    "outcoords", "usebpm",  "nsearch",  "search",  "rsearch",  "reject",
    "listcoords", " graphics", and "cursor".
    
    MSCGETCATALOG  is a new task that queries a web-based catalog server
    for coordinates and magnitudes of sources covered  by  one  or  more
    mosaic  exposures.   The task is an interim task to be eventually be
    replaced by general IRAF catalog access tools.  This  task  provides
    access  to  the USNO A2 catalog provided by two servers.  It is used
    to get coordinate lists  for  various  MSCRED  tasks  including  the
    on-the-fly feature of MSCCMATCH mentioned previously.
    
    MSCZERO  has  many new keystrokes as described by typing "?" for the
    cursor input.  Some of the new features  are  automatically  getting
    coordinates  to  mark  based on the MSCGETCATALOG task and selecting
    marked sources to use for the zero point adjustment.
    
    MSCFINDGAIN is a new task that implements the Janesick method  using
    two  flat  field  and  two  zero  exposures to estimate the gain and
    readout  noise  of  the  extensions  in  multiextension  mosaic  CCD 
    exposures.
    
    XTCOEFF  is a new task that estimates crosstalk coefficients between
    a source and victim extension.  It produces the information used  by
    the crosstalk correction calibration step in CCDPROC.
    
    CCDPROC  can  identify  saturated  pixels (defined in one of several
    ways) and produce an output bad pixel mask which  is  a  combination
    of  an  input  bad  pixel  mask (usually a static mask common to all
    exposures)  and  the  saturated  pixels.   The  new  parameters  are 
    "bpmasks" and "saturation".
    
    The minor enhancements involving parameter additions are as follows.
    MSCPUPIL has a new parameter "lmedian" which removes a  line-by-line
    median  prior  to fitting the pupil ghost.  MSCSETWCS has an equinox
    parameter to identify the keyword  for  the  equinox  of  the  right
    ascension  and  declination  keywords.   The WCS zeropoint is set to
    the right ascension and declination given by the keywords  precessed
    to 2000 from the equinox given by the equinox keyword.
    
    Finally  there  have  been  the  usual round of bug fixes and better
    handling of uncommon and error situations.




V3.2.3: November 24, 1999
    MSCDISPLAY was modified to use the "fill" parameter.  When  fill=yes
    then  the  display  buffer  will  be  filled.   This is the previous
    behavior.  If fill=no then the display buffer will tile  the  mosaic
    pieces  using  only  block  averaging  and  no  interpolation.  This
    avoids possible interpolation effects.  Note that  this  meaning  of
    fill=no is different than in DISPLAY.
    
    MSCIMAGE  was  modified to delete additional keywords from the final
    image which are inherited from one of the extensions but  which  are
    not  appropriate  for  a  single  image.  This is desirable to allow
    MSCDISPLAY to also display the single image correctly.

V3.2.2: November 17, 1999
    New tasks MSCSPLIT and MSCJOIN allow  splitting  and  rejoining  MEF
    files to/from separate images.
    
    MSCDISPLAY  now  makes  use of the "fill" parameter.  If fill=no the
    mosaic data will be block averaged to the  nearest  blocking  factor
    that  will fit in the display frame buffer.  Depending on the mosaic
    size and gap parameter values and the display frame buffer size  the
    amount  of  the frame buffer used will vary.  With fill=yes the same
    block averaging is done but then the result is interpolated to  fill
    the  display  frame buffer but preserving the aspect ratio.  This is
    the same result produced by  earlier  versions.   The  advantage  of
    fill=no  is  that  there  will  be  no  interpolation effects in the
    display.

V3.2.1: September 3, 1999
    MSCIMATCH  had  a  bug  that  if  iterative   rejection   was   used 
    (niterate>0)  then  a  floating  operand  error  would occur on some
    systems (Linux for  one).   MSCIMATCH  also  has  a  new  parameter,
    "measured",  that  should  be left blank for normal operation.  If a
    file  name  is  given  and  the  file  does  not  exist   then   the 
    measurements  used for the scale determinations will be written.  If
    the file exists, say from a previous execution,  the  file  will  be
    read  and  the  measurment  step will be skipped.  This is primarily
    for debugging but it potentially could be used to  input  photometry
    measurements obtained in some other way.

V3.2: August 27, 1999
    MSCCMATCH  was  modified  to  allow  a  slightly  more  general  and 
    appropriate solution for refraction distortions.  MSCDISPLAY  has  a
    modified  output  showing the individual scaling factors and what is
    actually  displayed.   MSCTVMARK  was  fixed  to  correctly   handle 
    untrimmed  data.   This  is  the version to be used at KPNO and CTIO
    during observing for the fall semester.

V3.1: June 17, 1999
    MSCSTACK was fixed to correct problem with the WCS  of  the  stacked
    image possibly being off depending on the order of the input images.

V3.1: June 11, 1999
    Changes  were  made  to  MSCCMATCH  to  fix  a problem when data are
    binned; specifically the logical and physical  coordinates  are  not
    the same.  For most people there is no need to get this update.

V3.1: June 8, 1999
    MSCIMAGE  would produce a finer pixel sampling if the input data was
    block averaged or observed with binning.  This was changed  so  that
    the  pixel  sampling  is  similar  between  the  input  data and the
    resampled data.

V3.1: June 3, 1999
    Problems with MSCTVMARK, MSCZERO,  and  MSCTPEAK  were  fixed.   The
    first  two  only  affect data with binning or that have been trimmed
    by CCDPROC.  MSCZERO would also produce wrong  results  after  doing
    an  'm'  to  mark coordinates from a file.  The latter now creates a
    coordinate database solution  that  can  be  directly  applied  with
    MSCSETWCS  without  having  to  edit  the  solution  fields  of  the 
    database.

V3.1: May 1999
    - RMFRINGE: New task to interactively remove a fringe image.
    - MSCSETWCS: New task to set WCS from astrometric database solution.
    - RMPUPIL: Parameter changes to skip initial automatic scaling if desired.
    - MSCEXAM: Fixed to work with data which has flips between extensions.
    - Fixed bug that would limit the number of MEF files that could be handled.

V3.0: April 1999
    The main areas of addition are:
    
    - Support for multiple amplifiers from the same CCD
    - Support for non-NOAO Mosaics
    - Bug fixes
    
    The new features are:
    
    - New task MSCPIXAREA to compute and apply pixel area correction from WCS.
    - New task MSCTVMARK to mark coordinates in MSCDISPLAY display.
    - New task MSCBLKAVG to block average mosaic data.  This includes proper
      updating of RDNOISE, GAIN, CCDSUM, etc.
    - New task MSCSKYSUB to fit and subtract a sky surface in the single
      mosaic images produced by MSCIMAGE; i.e. remove gradients prior to
      stacking.  The mean of the sky surface is not subtracted to keep the
      photon statistics roughly correct.
    - New default instrument translation file which can be used as a template
      for other sites.
    - CCDPROC now includes a crosstalk correction option.
    - MSCSTAT includes a global mode calculation.
    - MSCIMAGE uses the first extension as WCS reference if one is not given.
    - MSCRFITS/MSCWFITS aborts on a tape error.
    - RMPUPIL was improved to allow lists of images and some logging.
    - MSCIMATCH allows use of masks to exclude bad data and use of a SKYMEAN
      keyword constrain the relative zero level offsets while fitting the
      relative intensity scales.
    - Changes to CCDPROC to merge amplifiers from the same CCD into a single
      extension after processing.
    - Changes to CCDPROC to support relative flips between DATASEC and
      CCDSEC/DATASEC.
    - Changes to MSCDISPLAY to support relative flips between DATASEC and
      CCDSEC/DATASEC.  Also to support binning.
    - Changes to MSCZERO adding an 'r' key to reload the display and 'm' to
      mark objects from an RA/DEC list.  This uses new MSCTVMARK.
    - Change to CCDPROC to remove an error causing a string overflow in the
      expansion of the extensions.




V2.0: September 1998 (requires IRAF V2.11.1)
    This version has many  changes.   It  is  the  version  intended  to
    support  the  new  NOAO  Mosaic  Imager  with the science grade thin
    CCDs.  This is the version used by observers at NOAO  for  the  1998
    fall semester.
    
    - support for on-the-fly calibration during display
    - new tasks for dealing with the Mayall pupil image
    - mscdb is now a separate distribution outside of the mscred package
    - COMBINE can output a rejection mask showing which pixels in which
      images are rejected
    - CCDPROC has an optional output parameter
    - CCDPROC computes ccdmean value with sigma clipping
    - new faster and more sophisticated version of MSCIMATCH
    - SETINSTRUMENT is now organized by site and telescope
    - supports adding the IMMATCHX external package to allow sinc
      interpolation
    - new user's guide




V1.1: February 1998 (requires IRAF V2.11.1)
    The  software  now  uses  the V2.11.1 "tnx" world coordinate system.
    This is a image header representation of a tangent plane  projection
    plus  non-linear distortion terms.  This eliminates the need for the
    WCSSOL keyword to point to an external data file.  The  NOAO  Mosaic
    Data   Capture   Agent  will  produce  the  new  WCS  during  future 
    observations.  The software is backward compatible with  the  WCSSOL
    representation.
    
    MSCDISPLAY  has  a  new  parameter  to  allow display of a mosaic of
    separate images.

V1.0: January 1998
    New task MSCCMATCH matches (registers) the coordinate systems  using
    a  list  of common coordinates.  The WCS registration includes scale
    and rotation  adjustments  which  correct  for  differences  due  to
    atmospheric   refraction.    New   task  MSCIMATCH  intensity  match 
    individual constructed images for zero point and transparency  based
    on  photometry  of common objects.  A new task SFLATCOMBINE combines
    exposures to make a sky flat field.   SFLATCOMBINE  includes  a  new
    feature  of  COMBINE to provide a 2D rejection growing.  MSCZERO has
    more keystrokes and was made more efficient for adjusting a  set  of
    exposures  to  a common WCS zero point.  The MSCGUIDE was updated to
    this version.




V0.2: November 1997
    Improved MSCRFITS for quicker listing of  tapes,  new  COMBINE  that
    scales  Mosaic  images  with  the  same  scaling for all extensions,
    improved MSCZERO with '?'  help,  MSCEXAM  now  uses  full  database
    solution  for  world  coordinates,  new  tasks MSCCMD, MSCARITH, and
    MSCSTAT.

V0.1: September 1997
    First user and mosaic  developer  evaluation  version  with  minimal
    documentation.  Requires V2.11.

August 1997
    A  better  prototype.   This  release requires V2.11 (or V2.11Beta +
    patch1).  Help is skimpy.   Only  mscguide  and  imtextensions  have
    help.

November 1996
    This is a prototype.


INSTALLATION INSTRUCTIONS
Installation  of  this external package consists of obtaining the files,
creating a directory containing the package, compiling  the  executables
or  installing  precompiled executables, and defining the environment to
load and run the package.   For  NOAO  Mosaic  Imager  data  a  separate
instrument  database  distribution  also  needs  to  be  installed.  The
package may be installed for a site or as a personal  installation.   If
you   need   help   with   these   installation   instructions   contact  
iraf@noao.edu or call the IRAF HOTLINE at 520-318-8160.

[arch]
    In the following steps you will need to know the  IRAF  architecture
    identifier  for  your IRAF installation.  This identifier is similar
    to the host operating system type.  The identifiers are things  like
    "ssun"  for  Solaris, "alpha" for Dec Alpha, and "linux" or "redhat"
    for  most  Linux  systems.   The  IRAF  architecture  identifier  is 
    defined when you run IRAF.  Start the CL and then type
    
        cl> show arch
        .ssun
    
    This  is the value you need to know is without the leading '.'; i.e.
    the IRAF architecture is "ssun" in the above example.

[1-site]
    If you are installing the package for site use  login  as  IRAF  and
    edit the IRAF file defining the packages.
    
        % cd $hlib
    
    Define  the  environment  variables  mscred  and  mscdb  to  be  the 
    pathnames to the mscred package root directory  and  the  instrument
    database.   The  '$'  character  must be escaped in the VMS pathname
    and UNIX pathnames must be terminated with a '/'.   Edit  extern.pkg
    to include the following.
    
        reset mscred = /local/mscred/
        reset mscdb = /local/mscdb/
        task  mscred.pkg = mscred$mscred.cl
    
    Near  the  end of the hlib$extern.pkg file, update the definition of
    helpdb so it includes the mscred help database, copying  the  syntax
    already  used  in  the  string.   Add  this  line  before  the  line 
    containing a closing quote:
    
        ,mscred$lib/helpdb.mip\

[1-personal]
    If you are installing the package for personal  use  define  a  host
    environment  variable  with  the pathname of the directory where the
    package will be located (needed in order to build the  package  from
    the  source  code).   Note  that  pathnames  must end with '/'.  For
    example:
    
        % setenv mscred /local/mscred/
    
    In your login.cl or loginuser.cl file make the following definitions
    somewhere before the "keep" statement.
    
        reset mscred = /local/mscred/
        reset mscdb = /local/mscdb/
        task  mscred.pkg = mscred$mscred.cl
        printf ("reset helpdb=%s,mscred$lib/helpdb.mip\nkeep\n",
            envget("helpdb")) | cl
        flpr
    
    If  you  will  be  compiling the package, as opposed to installing a
    binary distribution, then you need  to  define  various  environment
    variables.   The  following  is  for  Unix/csh  which  is  the  main 
    supported environment.
    
        # Example
        % setenv iraf /iraf/iraf/             # Path to IRAF root (example)
        % source $iraf/unix/hlib/irafuser.csh # Define rest of environment
        % setenv IRAFARCH ssun                # IRAF architecture
    
    where  you  need  to  supply  the  appropriate  path  to  the   IRAF 
    installation  root  in  the  first  step  and  the IRAF architecture
    identifier for your machine in the last step.

[2] Login into IRAF.  Create a directory to contain  the  package  files
    and  the  instrument  database  files.   These  directory  should be
    outside the standard IRAF directory tree.
    
        cl> mkdir mscred$
        cl> mkdir mscdb$
        cl> cd mscred

[3] The package and instrument database are distributed as tar  archives
    for  the  sources  and, as an optional convenience, a tar archive of
    the executables for select host computers.  The instrument  database
    distribution   includes   calibration  files  for  the  NOAO  Mosaic 
    Imager.  For other instruments this file is not necessary though  it
    can  be  used  as  a  template for instrument files for your mosaic.
    Note that IRAF includes a tar reader.   The  tar  file(s)  are  most
    commonly  obtained  via  anonymous  ftp.  Below is an example from a
    Unix machine where the compressed files  have  the  ".Z"  extension.
    Files with ".gz" or ".tgz" can be handled similarly.
    
        cl> ftp iraf.noao.edu (140.252.1.1)
        login: anonymous
        password: [your email address]
        ftp> cd iraf/extern/mscred
        ftp> get mscred.readme
        ftp> binary
        ftp> get mscred.tar.Z
        ftp> get mscred-bin.<arch>.Z  (optional)
        ftp> cd ../mscdb
        ftp> get mscdb.tar.Z (optional)
        ftp> quit
        cl> !uncompress mscred.tar
        cl> !uncompress mscdb.tar (optional)
        cl> !uncompress mscred-bin.<arch> (optional)
    
    The  readme  file  contains  these  instructions.  The <arch> in the
    optional  executable  distribution   is   replaced   by   the   IRAF 
    architecture identification for your computer.
    
    Upon  request  the  tar file(s) may be otained on tape for a service
    charge.  In this case you would mount the tape use rtar  to  extract
    the tar files.

[4] Extract the source files from the tar archive using 'rtar".
    
        cl> softools
        so> rtar -xrf mscred.tar
        so> bye
    
    On  some  systems, an error message will appear ("Copy 'bin.generic'
    to './bin fails") which can be  ignored.   Sites  should  leave  the
    symbolic  link  'bin'  in  the  package  root  directory pointing to
    'bin.generic' but can delete any of the bin.<arch> directories  that
    won't  be  used.  If there is no binary directory for the system you
    are installing it will be  created  when  the  package  is  compiled
    later or when the binaries are installed.
    
    If the binary executables have been obtained these are now extracted
    into the appropriate bin.<arch> directory.
    
        # Example of sparc installation.
        cl> cd mscred
        cl> rtar -xrf mscred-bin.sparc      # Creates bin.sparc directory
    
    If the instrument database files  for  the  NOAO  Mosaic  have  been
    obtained extract these.
    
        cl> move mscdb.tar.Z mscdb$
        cl> cd mscdb
        cl> rtar -xf mscdb.tar

The  various  tar  files can be deleted once they have been successfully
installed.

[5] For a  source  installation  you  now  have  to  build  the  package
    executable(s).  First go to the package root directory with
    
        cl> cd mscred
    
    If  you  are  updating  to a newer version and you earlier built the
    libraries  and  executables  it  is  necessary  to   delete   these. 
    Otherwise,  depending  on  the dates of files in the new version and
    the locally built libraries, it may cause  the  new  version  to  be
    ignored.   To do this the package is configured "generic" which puts
    all the binary files in one binary directory, the files are  deleted
    and  then  you  continue  in  the  same  way  as  a  completely  new 
    installation.
    
        cl> mkpkg generic
        cl> delete bin.<arch>/*      # Substitute sparc, ssun, alpha, etc.
    
    Configure the package for the particular architecture to be built.
    
        cl> mkpkg <arch>            # Substitute sparc, ssun, alpha, etc.
    
    This will change the bin link from bin.generic to  bin.<arch>.   The
    binary  directory  will  be  created  if  not  present.  If an error
    occurs in setting the architecture then  you  may  need  to  add  an
    entry to the file "mkpkg".  Just follow the examples in the file.
    
    To create the executables and move them to the binary directory
    
        cl> mkpkg -p mscred         # build executables
        cl> mkpkg generic           # optionally restore generic setting
    
    Check  for  errors.   If the executables are not moved to the binary
    directory then step [1] to define the path for the package  was  not
    done  correctly.   The  last  step restores the package to a generic
    configuration.  This is not necessary if  you  will  only  have  one
    architecture for the package.

This  should  complete  the  installation.  You can now load the package
and begin testing and use.
