From farnham@palantir.astro.umd.edu Thu Aug 21 13:29:01 2003
Date: Thu, 21 Aug 2003 13:29:00 -0400 (EDT)
From: Tony Farnham <farnham@astro.umd.edu>
To: grayzeck@astro.umd.edu, raugh@astro.umd.edu
Subject: Annefrank data review
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Here are my comments about the AnneFrank data set from the Stardust
Navcam.  


In general, there is a wealth of documentation and information
available about the instrument, spacecraft, data sets, etc.  However,
some of this information is in the form of pdf and html files.  Much
of this is reproduced in ascii format, but not all of it.

The biggest problem that I could see was the lack of information in
the catalog files about the calibration procedures (both geometric
and photometric).  Calibration info all seems to be in pdf format in
the document files.  This even includes the description for converting
the 8-bit data to the 12-bit format.

I was able to read all of the full-frame images, and looked them over.
The cruise phase data are apparently ok, showing some stars and other
features.  Some of the "asteroid" images do not show the asteroid
itself, but the catalog files indicate that the pointing was off at
the start of the encounter.  Presumably these empty frames have value
in constraining the navigation and pointing abilities of the
spacecraft, which warrents their inclusion in the archive.  The
asteroid images look good.

I have not been able to read the sub-frame images yet (cruise phase data
in which only small subsections of the ccd image were downloaded).
Puneet has a technique that shows what is there, but we may need to
talk about how to best present this data.


Here are some more specific comments about the supporting files.

------------------------------------------------------------------------

In the documents section, some of the html files have figures that are not
included. (some are diagrams)


INST.CAT file:  

There is a statement:
   "All wavelengths are in nanometers. All filters have no requirements for
    lambda <3000 or >11000."

Otherwise, it appears that wavelengths are fairly conistently given in nm.

In the scan mirror section, the degree notation comes out as
"(".  also happens anywhere else degrees are used. (MISSION.CAT file seems
ok in this respect)

As written, there is a long section prepended at the start of the file
that describes warnings and problems involved with the instrument.  It
might be useful to include these warnings (or at least a comment
referring to the discussion at the start) in the sections sections
where they are relevant.


MISSION.CAT file 

Cruise 1 phase description:
   "The Cruise 1 phase of the first part of the STARDUST mission nearly six
    years long, relatively low activity cruise."
Is not a complete sentence and is confusing in that it sounds like the
cruise phase is six years long



INDEX.LBL

Description for column 27:
                    'A value of 1 indicates that sleep mode is enables
                     and a value of 0 indicates that sleep mode is
                     disables.'
should read (?)
                    'A value of 1 indicates that sleep mode is enabled
                     and a value of 0 indicates that sleep mode is
                     disabled.'

Column 41 and 42:  These are right ascension and declination, but does not
say of what.  Target? Center of image? 

Column 43:  Twist angle.  In what direction is this measured? CW or CCW?  

Column 48, 49, 50, 53, 54, 57: NOT_APPLICABLE_CONSTANT - I assume this the
value that the column displays when the variable is not applicable
(e.g. when the spacecraft is not approaching a target)?

Column 53 & 54:  Pixel Scales:  Are these pixel scales at the distance of
the target?  (e.g. the TARGET_CENTER_DISTANCE given in column 50)