MDM Trouble Report for 2013 Nov 01

Telescope: 2.4m
Observer(s): Adams, Simonian (The Ohio State University)
Instrument: OSMOS

Problem(s) Encountered:
We had issues with the edges of the CCD being saturated on the top and bottom edges despite the expected number of counts in the exposure being very low. These issues are intermittent, and usually go away when we move the telescope, but then come back unpredictably. We contacted Rick Pogge about this issue, and at his request took biases after a couple of these saturated artifacts to help diagnose the problem.

We also encountered a somewhat confusing issue where Prospero would complain when we set the region of interest to the 1k region. A sample output is shown below:
 pr> call roi1k

WARNING: Region-of-interest has been modified to maintain symmetry around CCD centerline.
 Error: Command returned error
WARNING: Region-of-interest has been modified to maintain symmetry around CCD centerline.
 Subroutine stack Line number:
 PROSPERO                0
 roi1k                   6
 Execution error in line  6
 Command: ic 'ROI 1525 2540 1525 2540 ON' silent
pr>

Despite the error, the region of interest still changes after starting an exposure. 

Other strange behavior is that when we called a script that changed the ROI, it aborted the execution in the middle due to what appears to be the above error:

pr> call fieldctr2r_adams
 Exposure time? 40

WARNING: Region-of-interest has been modified to maintain symmetry around CCD centerline.
 Error: Command returned error
WARNING: Region-of-interest has been modified to maintain symmetry around CCD centerline.
 Subroutine stack Line number:
 PROSPERO                0
 fieldctr2r_adams       15
 roi4x1k                 6
 Execution error in line  6
 Command: ic 'ROI 1 4064 1525 2540 ON' silent
pr>
 IC> WARNING: Region-of-interest has been modified to maintain symmetry around CCD centerline.

When the  call roi4x1k  line is commented out, it executes properly without aborting with the error above.

We also ran into problem with IC crashes. During an exposure, the routine would suddenly hang for an indefinite amount of time. When we interrupt the process with Ctrl+C, the prospero status showed that the IC was down, but then after running the  startup  command, it started working again. This happened twice within the course of the night.

Thank you, and good morning!

------------------------------

Submitted on 2013 Nov 2 [7:07:09]