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10 September 2003 

Present:   MJI, JRL, PSB, DWE, JMI

Apologies: STH

Agenda
------

1.   Actions from last meeting
2.   Comments on WFAU minutes
3.   Feedback from monthly Management Committee Meeting
4.   Interim report from DWE on tests on interleaving and interpolation
5.   Comments on the VISTA IR detector test procedure document
     /home/wfcam/public_html/internal/vdfsdocs/TestProcedure_020903.pdf
6.   Preparation for camera design review meeting
7.   AOB: (in)visibility of CASU web pages on new IoA web site


Minutes
-------

1.   Actions from last meeting

STH  no progress with Sandy Legget's data, ongoing                         <<<<

MJI  the pipeline milestones tasks and dates will be converted to html
JRL  and future updates will be done on the web.                           <<<<

MJI  is awaiting AA's return from holiday (re. UKIDSS Survey Manager)      <<<<

MJI  is updating Section 2. of DFS user requirements document. This needs 
     to be finished before the Camera Design Review (next week).           <<<<

JMI  comments were sent to JMI about his three reports

ALL  sent monthly reports to STH

MJI  wrote intro for difference imaging report

STH  needs to write a context intro for simulation report                  <<<<

JMI  incorporated feedback into his documents and linked them from public 
     web page. DWE asked JMI for his comments regarding HTML as a format 
     for documentation and he strongly advised against it if the document 
     requires a lot of figure numbering. Latex-based documents are a 
     suitable alternative.  If web documents are required latex2html or 
     tth can be used.

STH  it was unknown whether Paul Hirst or Andy Adamson had been emailed 
     concerning the the setting up of the photometric standards fields 
     within the characterization plan.  Additionally DWE should email      
     STH with his additions so that these can be put forward at the 
     same time.                                                            <<<<
     PSB raised the issue of photometric standards for VISTA. STH should
     extend the number of fields that he has established for WFCAM to the
     south for use by VISTA so that PSB can incorporate within his 
     calibration plan document                                             <<<<

JRL  sent comments to PSB about the FITS headers document. There was some
     further discussion and clarification regarding some of these points.

ALL  various people had read the ESO documents and sent comments to PSB


2.   Comments on WFAU minutes

No new minutes were available since the previous CASU meeting, so there
were no comments.


3.   Feedback from monthly Management Committee Meeting

The next meeting will be 1 October. The end of quarter reports need to be 
in before this (before 26th September to give STH time to absorb them). 
All to review our Q3 deliverables in order to maximize our completions.    <<<<

MJI pointed out that this will be an important meeting since it comes
shortly before the Oversight Committee's next review (10 October?) which
is pertinent for the next release of cash and the e-science II bid.

One of the requests from the MCM was that the documentation web page
should have release and revised dates next to each entry. 
DWE said that he would do this.                                            <<<<


4.   Interim report from DWE on tests on interleaving and interpolation

DWE showed some plots from his recent work on interleaving and interpolation.

Astrometric and photometric error plots for various scenarios involving 
interleaving were shown. The 4 cases were: no interleaving, interleaving (2x2)
with idealized seeing, realistic seeing, and bad seeing (these all refer to
the stability of the seeing). At the bright end, interleaving in all cases
produces astrometry twice as accurate as that with no interleaving. 
For these tests for bright objects 2x2 interleaving gives coordinates 
accurate to about 15 mas, while the non-interleaved data limits at around
30 mas.  At the faint end no difference is seen due to the errors being 
dominated by Poisson noise. The significant finding is that the interleaving 
results are broadly similar even if the seeing is not stable ie. interleaving 
works in poor conditions (using weighted centroiding).

The photometric errors were the same in all 4 cases. This is mainly due to
the pixels acting like light buckets and negligible changes in overall PSF
scale.

Examples of interleaved images were shown. The bad seeing case showed the
expected "hedgehog" features, which would cause grief for most PSF fitting 
techniques. 

A demonstration was also shown on how useful interleaving (3x3) might be at
showing additional detail. It was suggested that an equivalent plot for 2x2
also be carried out and posted on the web pages.                           <<<<

MJI suggested looking at the 2MASS web pages for more information on 
"interleaving" results.                                                    <<<<

More studies and a report on all this will be written shortly.             <<<<

Emanuel Bertin has supplied a beta release of SWarp (v2.0) which has been
installed on cmt05. This should be faster code. Initial tests were mixed. 
In general, SWarp has been tamed and shifts and rotations can be made as
required. This will be used in the testing of various aspects of
interpolation.


5.   Comments on the VISTA IR detector test procedure document
     /home/wfcam/public_html/internal/vdfsdocs/TestProcedure_020903.pdf

MJI said that feedback was required on the above document by the end of the
week.                                                                      <<<<

The following were comments regarding the document that were raised during 
the meeting:
i   No intrapixel sensitivity tests.
ii  Unclear whether there where any reset anomaly tests.
iii It was felt that the document just listed a set of things to measure 
    with no suggestions on what to do if any of these parameters were 
    problematic.
iv  A cross-reference is required to the requirements.

It was stressed that there was a need for doing these tests in the
laboratory. Carrying them out on the telescope was felt to be unacceptable.
Concern was expressed about the possibility that laboratory tests like these
could be cancelled in order to save money.


6.   Preparation for camera design review meeting

PSB will attend this meeting for all 3 days while MJI and JRL will attend
for most of Thursday and Friday. During this time it is expected that the
CASU team will give about a 1 hour presentation. Jim Emerson will also give
an introductory overview talk.

There was some uncertainty regarding the details of this meeting. PSB said
that he would sort out the accommodation requirements and look into the
agenda and where within RAL the meeting would be held.                     <<<<


7.   AOB: (in)visibility of CASU web pages on new IoA web site 

CASU seems to have dropped off the radar with the new web site. DWE will
email Andy Batey to enhance CASU's web presence.                           <<<<

It was noted that the WFS progress web pages have not been correctly 
updated for some time.   Since this is regarded as a proto-WFCAM 
pipeline progress monitoring system, STH needs to update the scripts.      <<<<

There were a number of requests for an overview of the VISTA IR camera
design. PSB said that he has seen a web page containing this information. 
He said that he would locate the page and pass on the information.         <<<<

Hardware news: 2 desktops (JRL and STH) plus HP DDS5 (72) have been ordered, 
(delivered and tested in the latter case) as well as an Overland 17 slot 
LT02 tape drive system.  It is now time to spec. and order the front-end 
data server PC for the LTO tape drive et al.                               <<<<
[Note added after meeting: further successful compatibility tests between 
 different LTO-I and -II systems were carried out on our behalf by our
 supplier.]

There is no news regarding our contracts - 5 months 1 week late and counting...


Continuing Actions
------------------

STH  check Sandy Legget's data and (probably) send in a request for more 
     data.
     
JMI  to update and convert pipeline milestones tasks and dates document 
MJI  to HTML.
JRL

MJI  await reply from AA concerning the UKIDSS Survey Manager appointment on 
     Hawaii.
     
MJI  continue updating Section 2. of DFS user requirements document.
     This needs to be finished by the Camera Design Review (next week).

STH  write context intro for simulation report

STH  email Paul Hirst or Andy Adamson concerning the setting up of the 
     photometric standards fields within the characterization plan.


New Actions
-----------

DWE  email STH with his additions to the characterization plan so that these 
     could be suggested at the same time as the above.

STH  extend the number of fields that he has established for WFCAM to the
     south for use by VISTA.

DWE  alter the documentation web page so that there are release and revised 
     dates next to each entry. 

DWE  do equivalent 2x2 interleaving plots cf. 3x3 demonstration and place
     results on web

DWE  to investigate the 2MASS web pages for examples of "interleaving"
     efficacy

DWE  write report on interleaving work

MJI  provide feedback on VISTA IR detector test procedure document by the 
JRL  end of the week.
PSB

PSB  sort out the accommodation, agenda and exact location for CDR meeting 
     at RAL

DWE  email Andy Batey to request a link to CASU from the research page of 
     the IoA web site

STH  update the prototype pipeline progress (WFS) scripts and web pages
JMI

PSB  locate the web page containing the overview of the VISTA IR camera 
     design and pass on the information

PSB  spec and order a rack-mountable data server PC to go with the recently 
MJI  ordered LT02 tape drive unit