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problem with a bright column

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#1 prefetch

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Posted 02 June 2020 - 11:44 PM

i've been using an ML50100 camera recently and i'm having trouble processing the frames because of this one bright column in the CCD that i can't seem to process away.

 

normally i have problems with dark columns, and i use pixinsight cosmetic correction to handle them, but this a bright column, and an application of cosmetic correction seem to have no effect on it.

 

i've tried to run ImageIntegration with various types of combination routines (average, median, maximum, minimum) but none of them seem to help.  the bright column is present on all frames, independent of filter used and it is present in the same numbered column on all frames, so i'm very confident it's a CCD issue.

 

has anyone run into this kind of CCD problem before?  any ideas?

 

here is a single frame:

EXDW9A3.png

 

here is the image after stacking with ImageIntegration:

 

fbM3uC4.png



#2 happylimpet

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Posted 03 June 2020 - 01:48 AM

Surely dark frames will remove this? You dont mention them.



#3 pyrasanth

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Posted 03 June 2020 - 01:59 AM

Try the creation of a defect list in PI along with a dark. This should remove the column.,



#4 terry59

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Posted 03 June 2020 - 05:57 AM

Try the creation of a defect list in PI along with a dark. This should remove the column.,

+1...and save the process off so you don't need to recreate it every time



#5 ChrisWhite

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Posted 03 June 2020 - 06:11 AM

You can map this out with cosmetic correction.  You would need to define the x/y coordinates of the defect but it will remove this.  If you want me to do it for you so you can see exactly where the settings are in the tool feel free to PM me with a link to the file.  I'll update you with a cosmetic correction process icon.  It can be confusing to figure it out the first time, but once you see it you would understand how to do it in the future. 


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#6 prefetch

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Posted 03 June 2020 - 06:14 PM

thanks guys!  it's fixed now.

 

it looks like i didn't include a master dark in the cosmetic correction process.

 

i usually calibrate and integrate "by hand" instead of using the batch process, but i thought i'd try the new batch process out and in doing so i sorta got turned around on things because the batch process creates the master dark, and you can't include that master dark in the cosmetic correction process because it hasn't been created yet...kinda circular, right?  or maybe i'm not doing something right.

 

thanks again everyone.  clear skies! smile.gif


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