Staff Assigned: Tim sudden contamination on E2V chip during run

Discussion in 'Aluma CCD Series' started by Richard S Post, Jul 6, 2019.

  1. Richard S Post

    Richard S Post Cyanogen Customer

    Joined:
    Oct 11, 2014
    Messages:
    81
    Doug,
    I run a remote observatory and the Aluma 47-10 was getting nice images at 3:15 am, 6/24, when MDL crashed as seen in a previously posting. At 4 am, I restart MDL and ACP to continue the run. On the first image, I noticed what looks like condensation. 2 min later on the next image, the artifacts were larger, so I stopped the run and warmed the detector. The next day, I took a room temperature image using the observatory light on illuminating the wall. The image shows what looks like large particles and stains on the detector. After 2 weeks, I took room and -20C images with large particles showing, but no condensation.

    I have attached 5 images with the following time sequence: a good image before MDL crashed, image showing condensation like spots upon restart and the subsequent image, the image taken the following day and an image taken today.

    I will be at the obseratory for a week, next week. I can do further tests if you wish. The camera can't be used until it can be fixed.

    Regards, Dick
     

    Attached Files:

  2. Colin Haig

    Colin Haig Staff Member

    Joined:
    Oct 27, 2014
    Messages:
    7,379
    Location:
    Earth
    Dick, one of my colleagues will get back to you. We're reviewing.
    Best wishes,
    Colin
     
  3. Tim

    Tim Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    1,841
    I have not seen that type of artifact before on these sensors. Please send it back at your convenience and we will investigate further.

    I will send you the return instructions via PM shortly.
     
  4. Richard S Post

    Richard S Post Cyanogen Customer

    Joined:
    Oct 11, 2014
    Messages:
    81
    I recieved a note that my camera is repaired, but it has not arrived. Could I get the tracking number?

    Can you explain the source of the problem and its solution?

    Thanks, Dick
     
  5. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    9,932
    It looks like some of the thermal pad material migrated. Not sure why that happened but we have changed to a different material so it shouldn’t happen again.

    I’ll check with our shipping department.
     
  6. Richard S Post

    Richard S Post Cyanogen Customer

    Joined:
    Oct 11, 2014
    Messages:
    81
    I just got up to Maine for the holidays and installed the repaired camera. Before installing, I look to see that the sensor chamber was free of dust and saw a crack in the middle of the window. The shipment had arrive with no sign of damage to the package, so I don't see this as result of shipment. It was never dropped by me or experienced any shock that could have cause this. I would seem that the window was stressed with non-uniform pressure. I can send a wll shot to see the effect on the image.
     

    Attached Files:

  7. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    9,932
    That's truly strange; we've never had an Aluma window crack before, and it's hard to understand how that would happen. Also strange that it appears perfectly straight and horizontal. Sounds like it will have to come back again. I'll ask Tim to follow up with you.
     
  8. Tim

    Tim Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    1,841
    PM with RMA details sent.
     
  9. Richard S Post

    Richard S Post Cyanogen Customer

    Joined:
    Oct 11, 2014
    Messages:
    81
    Any update?
    Dick
     
  10. Richard S Post

    Richard S Post Cyanogen Customer

    Joined:
    Oct 11, 2014
    Messages:
    81
    It has been a month and I have not heard anything about the repair. When will the camera be repaired? Do you understand the reason for the window crack?
    Thanks, Dick
     
  11. Tim

    Tim Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    1,841
    PM sent
     

Share This Page