Problem(s) Encountered:

An issue that popped up again last night was on a few exposures, the guide star would start moving around in the window very erratically and either start doing a counter-clockwise rotation or once it left the field completely and the guider switched to another guide star half way through the exposure. When this happen it normally ruined the exposure and had to be retaken. I have left the graph for the last star we used for guiding up on the guider screen so the 2.4 support staff can take a quick look at to see the error in the x and y.

Solutions:

The rotation angle (changed under the settings option on the guide tab) is set by the following equation:

angle = -90 - rotator angle

Since observations were being performed with the rotator set to 0, the angle should have been -90.  It was instead set to around -13.  In retrospect, I''m surprised the guider was working for them as well as it was.  The number has since been changed to -90 in preparation for tonight''s observations.