MDM Trouble Report for 2015 Nov 11

Telescope: 2.4m
Observer(s): Ryan Chornock (Ohio University)
Instrument: OSMOS/R

Problem(s) Encountered:

The main problem I encountered was that the rotator hit the limit and stopped working.  I was observing a target where the parallactic angle was near -77 deg, which should be within the limits of the rotator.  I was out in the dome rotating from a PA near zero to that angle and I heard a sound and was then unable to rotate back any more (i.e., back towards PA=0 deg, not the direction I was going). I tried going back and forth in both directions but all that did was to move up to the limit of -85 deg.
This was near the end of the night, so I just used PA=-85 for the remaining objects and I left the telescope in that rotated position.  

Early in the night, a few images did not show up in the data directory after being displayed by the data-taking software and not generating a visible error.  I noticed this soon enough, so looked and saw an error in the Caliban console about not being able to copy a file and eventually Prospero also had some IS error.  I just killed and restarted the ISIS/Caliban/prospero software and everything was fine afterward.  Fortunately, the missing files were not science files (arc lamp + alignment image).

Also, I was using John Thorstensen's osctrtask to put objects in the slit (using  option 2  from the webpage-- enter the dy/dx in small increments and watch the guiding pull the telescope in the right direction).  As I found last month, the computed dy increments can be added to the probe y position, but the dx values have the opposite sign. (so if the task tells me dx=XX and dY=YY, I enter YY into the dY box but -XX into the dx box).


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Submitted on 2015 Nov 12 [11:46:30]