MDM Trouble Report for 2012 Mar 16

Telescope: 1.3m
Observer(s): Skowron (OSU)
Instrument: CCDS

Problem(s) Encountered:
Telescope was jumping in N/S direction quite a bit today. Most often close to zenith (eg. ha=00:25 dec=25.03, or ha=-0.08 dec=16.14) and on the West near airmass 2.0 (ha=2.32 dec=-10.21).
One exposure was ruined by this, in my opinion. And other time I had to skip one object and come back to it later at night because of this issue - it was hard to observe in this direction.
Amplitude of jumps is usually ~ 60 arcseconds. Only few times this resulted in loosing the guide star from the square.

Also I had once again a problem with ability to move the telescope in N/S direction using software paddle. Putting 30.0 arcsec would move by ~<10 arcsec. Putting small number seams not to move at all. 
This issue comes and goes. I have an impression that the more I use the paddle in the short intervals of time the bigger the chances of this happening. Today this happened only once, probably because most of the small movements of the telescope I was doing using the Guider not the paddle.
E/W direction works fine.

I have noticed, that the plastic band holding a rubber pipe to the metal pipe in the silver/gray LN2 tank does not hold tightly, so LN2 sprays upwards a little bit from this connection during the filling process. Probably new plastic band would fix this. 


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Submitted on 2012 Mar 17 [6:29:45]