Staff Assigned: Tim Bizarre Images from Aluma 8300

Discussion in 'Aluma CCD Series' started by Greg Crawford, Jan 27, 2020.

  1. Greg Crawford

    Greg Crawford Cyanogen Customer

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    I am getting very strange images from my Aluma 8300. I will upload an image. The white lines and the zig-zag marks move around when images are taken in sequences. Does anyone recognise the symptoms of something?
     

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  2. Colin Haig

    Colin Haig Staff Member

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    I'll get our guys to have a look at this. It looks like the image data is being clocked out of the chip incorrrectly and so it is skewed.
    Do you have the original image (not bias and dark subtracted)?
    I see the temperature delta was about 56C.
     
  3. Greg Crawford

    Greg Crawford Cyanogen Customer

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    A little further experimentation: If I turn off the cooling, the bizarre behaviour stops. I don't think it has anything to do with frosting. First, whenever I've seen the effects of frost, it doesn't look like this. Second, the return to normal when cooling is turned off occurs in about 5 seconds, not the gradual loss of frost that would occur as the glass gradually warmed up. My speculation - the power required for cooling causes some other component to go off spec. I'll take another image at a cooled temperature without calibration frames and upload it here.
     
  4. Colin Haig

    Colin Haig Staff Member

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    Are you running with the originally supplied AC power pack, or your own 12VDC source?
     
  5. Doug

    Doug Staff Member

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    Yes an uncalibrated FITS image would be helpful. Also please provide your camera serial number.
     
  6. Greg Crawford

    Greg Crawford Cyanogen Customer

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    OK. Here are some uncalibrated images. Basically, as the cooler power required increased, the offset of the image to the right of the frame appeared, with a white "dog's leg" appearing on the left of the image. If I gradually decreased the temperature so that the cooler power could remain at a low level, the problem did not occur until the temperature was low enough for the cooler power to remain at a higher level. According to the DL Config software, the serial number is: AL8300M-19021501
     

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  7. Doug

    Doug Staff Member

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    What firmware are you running?
     
  8. Doug

    Doug Staff Member

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    We test all camera designs at -30C and +40C ambient, to make sure that no problems crop up at temperature extremes. We have a couple of Aluma 8300's on the shelf so we just ran the test again, and we did not get the problem. So this appears to be something specific to your camera.

    I'll pass this over to @Tim
     
  9. Tim

    Tim Staff Member

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    PM sent
     

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