Date: Thu, 20 Oct 2005 11:51:31 -0500
From: "Eric H. Neilsen, Jr."
Subject: Re: 2.5m obslog 20051019 (MJD 53663)
Russell-
Something went wrong at the beginning of the run, before the first frame
was taken. Even the RA is wrong in the idReport file, iop gets this
value from the DA before the run starts. iop was confused about the
xBore and yBore all the way through because of this, but it isn't clear
how this confusion propogates into the DA, because frames are written
independently of iop.
    -Eric
Russell E Owen wrote:
> At 1:48 PM +0000 2005-10-20, observer@sdsshost2.apo.nmsu.edu wrote:
>
>> ...Apparently there was a
>> problem getting the right value for RA, xbore and ybore at the
>> beginning of
>> the drift that affected the xbore, ybore output to the gang headers.
>> After we
>> realized this, we opted to end the drift and back up and start a new
>> drift to
>> see if the problem repeated itself. It did not. Why was the
>> information bad at
>> the beginning of the drift? We don't know at this point. Russell,
>> could it be
>> related to the TCC change to Multinet 5.1?
>>
>> 04:05Z ended drift at frame 261, lambda 149.5
>> Seeing was good throughout run 5743 (Often subarcsec). Skies were
>> photometric.
>> In spite of the lack of skippy data, pointing was almost certainly
>> good. Gang
>> headers will need to be edited to correct the wrong xbore, ybore values.
>>
>> Note that the RA in the gang headers was good from the beginning,
>> xbore and
>> ybore were -9999 from the beginning.
>
>
> It seems strange that RA was OK but xbore and ybore were not OK. From
> that, I suspect an internal DA problem, rather than the TCC. But I
> don't know enough about the internals of the system to trust that guess.
>
> Is there any direct way to test if the DA system is getting the TCC's
> UDP packets and is happy with them? Does the system complain if it's
> not getting the info? If not, can it be made to do so?
>
> -- Russell
>
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