Resolved SBIG STF-8300M, noisy and uneven darks after fw update

Discussion in 'STF Series CCD Cameras' started by Georg Papp, Apr 4, 2021.

  1. Georg Papp

    Georg Papp Standard User

    Joined:
    Apr 3, 2021
    Messages:
    4
    I suspect that something has gone wrong on my SBIG STF-8300 M. From one day to the other, the histogram for all subs suddenly started at arount 17 000. After I updated the firmware to the latest version, the histogram went down to start around 1000 and I thought everything was ok. But when I compare a 10 min dark sub with a dark taken before the problem arose, the new subs look much noisier and not as even over the whole picture. What could be the cause and is there a solution? The serial number is 83F010724.

    Help is welcome,

    George from Sweden
     

    Attached Files:

  2. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    9,932
    It basically looks normal, but it looks like there is some light contamination on the April image. If you took the light frame in daytime there could have been some light leaking around the shutter - these cameras are extremely sensitive.
     
  3. Georg Papp

    Georg Papp Standard User

    Joined:
    Apr 3, 2021
    Messages:
    4
    You are absolutely right. I confirmed by taking a new dark with the camera in total darkness and now the dark-sub is completely even. I'm so relieved that there was nothing wrong, and that the firmware upgrade actually fixed the histogram problem. A curious question, what is the normal value for Gain? I see that my camera has a value of 2.30, but I have seen that other people's cameras can be as low as 0.37.
     
  4. Doug

    Doug Staff Member

    Joined:
    Sep 25, 2014
    Messages:
    9,932
    It sounds like your camera's EEPROM may have been messed up a little. That's not a normal value for gain. It doesn't mean your camera isn't producing correct images, though; it just means it's displaying the wrong gain value.

    We can probably fix that for you remotely. I'll check with the team on that.
     
    Georg Papp likes this.
  5. Adam Robichaud

    Adam Robichaud Lead Developer Staff Member

    Joined:
    Sep 29, 2014
    Messages:
    1,012
    Location:
    Ottawa
    Hi Georg, I can fix that for you, but I'll need two things:
    1. Can you confirm your serial number for me? The one you provided up-thread isn't showing up in our records.
    2. I'll need your TeamViewer connection details (in a private message please)
     
  6. Georg Papp

    Georg Papp Standard User

    Joined:
    Apr 3, 2021
    Messages:
    4
    Thanks! You have PM.
     
  7. Adam Robichaud

    Adam Robichaud Lead Developer Staff Member

    Joined:
    Sep 29, 2014
    Messages:
    1,012
    Location:
    Ottawa
    I was able to log into Georg's computer and do some troubleshooting. His EEPROM was missing an eGain and serial number entry, but the camera's AD converter was otherwise performing according to spec. I've updated his EEPROM to include a nominal eGain value, and the label's serial number, and verified that bias levels and gains were where they should be without cooling.
     
    Tim Povlick likes this.
  8. Georg Papp

    Georg Papp Standard User

    Joined:
    Apr 3, 2021
    Messages:
    4
    Problem solved. Just want to express my gratitude for your fantastic support, absolutely incredible.
     
    Adam Robichaud likes this.

Share This Page