PDS NEAR higher level data review, meeting notes.
August 15, 2001.

NIS
===

Starting at 3:10 pm.

Mike Belton leads the NIS review.  Noam I. from APL joins by telecon.
Pretty comprehensive data set.

Mike complains that it took days to even figure out how to read the
huge data file.  He used fv.  It takes 8 minutes to read in the data.
He suggests it might be broken into smaller files.

When the fits viewer displays the data, it says it is an image but it is
not, it's a table.  

Mike could not find how to relate an individual spectrum to the documented
observing sequences.  How to figure out what each spectrum is looking at.

Mike had a hard time finding the niscal documentation.  He couldn't find
definitions of the parameters.

Mike suggests that spectra should be stored in columns, not in rows.
(not possible in PDS.)

This data structure basically requires IDL.  It is very difficult to view
otherwise.

Dan says imaging spectroscopy is too complex to be available to the casual
user.  

Much brainstorming about how the data structure can be modified to make the
data easier to use.

-->  Clarify language in errata.txt.

Calibration documentation doesn't describe what the calibration spectra
look like or what they are spectra of.  Nothing tells what the calibration
plaque is.  Noam says you are supposed to read the calibration paper.

-->  Need to adequately explain the columns in the data on the circumstances
of each observation such as sequence description, whether an observation is
a calibration, what the calibration target is, instrument mode, etc.  This
information to be placed in an easily accessible place in the calib
directory.  (columns 3-13).  Also place in the column descriptions in the
label.

-->  Place a brief description of the calibration target in the data set cat.

Integrity of the data is good.  

-->  Brian Carcich offers to look into breaking the NIS data file into
smaller chunks.  This is a low priority lien and if unforseen difficulties
arise it will be dropped.  Index tables would be required.  There is a limit
on the number of files per directory so the thousands of files will have to
be broken down into subdirectories.

NIS level 3:

Very useful products.  However, there are no spectra in the level 3 submission.
Maybe some effort should be made to create a browse file of spectra to see
roughly how the spectrum changes over the disk.  Real spectra in a browse
thumbnail arrangement.  As few as three or four spectra would be helpful.

-->  Look into the possibility of providing a browse directory with
one or more sample spectra in image form.  This is a low-priority lien
which may be dropped if it becomes too difficult.

-->  Put a copy of the database table on volume 2 (without the links) onto
volume 1 with a reference to the existence of the linked table on volume 2.

Mike says he can't play the movies on his Mac.  Everyone tries and some
can play it and some can't.  This is not a lien.  

Copies of liens to Brian, Noam, Howard, and Kopal.


We finished at 4:30 pm.