Source of Hot Pixel Readout Line ?.

[iosman123]

Hello,

I've been struggling with a "hot pixel readout" line that sometimes appears in my lights and darks, and I've been trying to determine what causes the line to appear sometimes, and not appear other times.  I have been told that these hot pixel readout lines are not uncommon in CCDs (I have Atik 383L+ camera).  I have attached an dark that shows the line I'm talking about. For example, last night I took 7 lights, and then after the clouds rolled in I took 33 darks. None of the lights showed the hot pixel readout line. The first 12 darks also did not show the line, but the remaining 21 darks did show the line clearly. Also, a few days ago I took some lights of the same object, and those lights all DID show the line. So it seems as though this line comes and goes.

Does anyone know potential causes for these lines or how to reduce the likelihood of them appearing? The good news is that these lines do calibrate out, but I have to keep a library of darks WITH the line, and a library of darks WITHOUT the line, and then I have to examine each light sub directly to see if it has the line or not, and then match the darks to the lights. I sure would like to eliminate the line so I don't have to go through all this every time.


thanks
jackyjoy