Subject: Re: [sloan-25mlog 3238] Re: 2.5m obslog 20161129 (SJD 57722)
From: Viktor Malanushenko
Date: Wed, 30 Nov 2016 15:13:14 -0700
Hi Dan,
Thanks for the advice. I'll try this option tonight. Of course, if this =
situation persists.=20
Tonight I=92ll warm observer.
:)
Viktor Malanushenko
viktorm@apo.nmsu.edu
> On Nov 30, 2016, at 3:04 PM, Dan Long  wrote:
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> Hi Viktor,
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>    If you see fiducial errors too large to correct in azimuth after =
missing several fiducials in a row, and the errors are on the order of a =
few thousand ticks and look similar to each other once you start reading =
again, it is a pretty good bet that the error is real and if you force a =
correction on azimuth you will see guide stars.
>   It would also be quicker than slewing again, especially if you are =
missing multiple fiducials in a row (since you might end up with the =
same large error if they don=92t register a crossing on the next slew =
attempt).
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> 		Cheers,
>=20
> 		   Dan
> On Nov 30, 2016, at 2:32 PM, Viktor Malanushenko =
 wrote:
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>> Hi Dan,
>>=20
>> We did not do a forcing correction fiducials. We just move the =
telescope in azimuth to locate the correct intersection fiducials.=20
>> Then we repeated the =91goto field=92 of the telescope.=20
>> Telescope come to the correct position with an accuracy of about 10 =
arcsec, without additional offsets.
>>=20
>> Thanks,
>>=20
>> Viktor Malanushenko
>> viktorm@apo.nmsu.edu
>>=20
>>=20
>>=20
>>> On Nov 30, 2016, at 2:25 PM, Dan Long  wrote:
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>>> Hi Viktor,
>>>=20
>>> =46rom the amount of time lost it appears that accepting the =
fiducial error (forcing a correction) at the end of the slew did not fix =
the problem, and get guide stars to show up?
>>>=20
>>> Here is an excerpt from the tron log.  The errors were too large to =
correct after the gap between registered fiducials, but seem consistent =
with a real error due to the scale of azimuth being sufficiently wrong =
and then missing several fiducials in a row. =20
>>>=20
>>>=20
>>> 2016-11-30 11:05:03.1130Z >> 2016-11-30 11:05:10.6002Z >> 2016-11-30 11:05:18.0960Z >> 2016-11-30 11:11:51.8929Z >> 2016-11-30 11:11:59.4156Z >> 2016-11-30 11:12:06.9885Z >>=20
>>> 		Cheers,
>>>=20
>>> 		   Dan
>>>=20
>>>=20
>>> On Nov 30, 2016, at 1:45 PM, Viktor Malanushenko =
 wrote:
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>>>> Hi Kaike,
>>>> fiducial errors was approx between 6000-7000 .
>>>> So we could not found guiding stars.
>>>>=20
>>>> Viktor Malanushenko
>>>> viktorm@apo.nmsu.edu
>>>>=20
>>>>=20
>>>>=20
>>>>> On Nov 30, 2016, at 7:52 AM, Kaike Pan  wrote:
>>>>>=20
>>>>>=20
>>>>>>=20
>>>>>> Lost time:=20
>>>>>> -- due to weather (high humidity): eBOSS: 1.8 hours
>>>>>> -- due to hardware (Az fiducials) 15 min
>>>>>>=20
>>>>>>=20
>>>>>>=20
>>>>>>=20
>>>>>>=20
>>>>>>=20
>>>>>>=20
>>>>>>=20
>>>>>> 11:05:35  apogee.expose=3DapRaw-21600033, 10, B, Dark
>>>>>> 11:07:23  apogee.expose=3DapRaw-21600034, 10, B, Dark
>>>>>> ----------------------------------------
>>>>>> 11:08:49  loadCart: Cart 4, Plate 8938; GSoGTF=20
>>>>>> 11:08:49 survey: APOGEE-2&MaNGA;  lead: MaNGA dither
>>>>>>=20
>>>>>> -- was many fiducials error of Az. We lost 15 min to adjust it.
>>>>>> After adjusting - guider stars coming on go to field.
>>>>>>=20
>>>>>=20
>>>>> Hi Viktor and Katie,
>>>>> Can you please the problem with more details: how big the fiducial =
errors
>>>>> are and what you did to resolve it? Thanks
>>>>>=20
>>>>=20
>>>> ____________________________________________________________
>>>> Logs of Nightly APO Activities
>>>> =
https://trac.sdss.org/tracmailman/browser/private/sloan-25mlog/index.html
>>>=20
>>=20
>> ____________________________________________________________
>> Logs of Nightly APO Activities
>> =
https://trac.sdss.org/tracmailman/browser/private/sloan-25mlog/index.html
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