PR 2559: Dewar 3 iced up and occasionally complaining of ln2temp, ln2 empty

The blue dewar on spectrograph two ( CCD03 ) has a large ice build-up.  About 
every hour and a half there is an error that the ln2 is empty along with an 
ln2temp error.  Looking at the ln2temp plot one sees five or six data points 
around the nominal temperature of 92 K, followed by one point somewhere 
between 110 and 120 K.  It looks like the fill interval is just slightly 
longer than the hold time.  None of the other dewars are showing this behavior.

Is is possible the vacuum isn't what it should be, or maybe there is a leak 
in the fill tube where it connects to the dewar, leading to inefficient or 
incomplete fills?


PR 2560: Twice in two days M2 actuator E couldn't stop on a full step.

In the last two days, each time early in the evening, we started getting 
errors from the M2 galil when it attempted to adjust the collimation of the 
secondary during tracking.  The galil was complaining that it could not get 
actuator E to stop on a full step.

0 0 F Modu="mir_o_MoveOneGalil"; Text=" Sec returned an error message"
0 0 I Received="?GOCORR one or more axes did not end on a full step  0,  0,  
0,  0,  1"
0 0 W Text="failed to adjust collimation and focus"

In both cases homing the E axis restored operation and it kept working the 
rest of the night.