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Starnet - not dust motes but looks similar

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#1 Becomart

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Posted 24 May 2020 - 03:38 PM

I’ve been playing around with different techniques before beginning a process on my elephant trunk nebula....using starnet on each individual channel and seeing if there is a difference when using starnet on a combined image. All good curiosity. 
 

I’ve noticed whatever method I use that I get purple rings like dust motes in some parts of the image with a slightly mottled looking background where this occurs. Examining the raw stacks, expected to see a flats issue but can see any sign of motes if under an extreme stretch..everything looks normal. Anybody else experienced this and know what the cause and solution (apart from clone stamping) is?



#2 Der_Pit

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Posted 24 May 2020 - 04:56 PM

Variations in seeing?  Variable stars?



#3 Becomart

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Posted 25 May 2020 - 05:26 AM

Below is an example of what I'm seeing and it does seem to be occurring around brighter stars. This is a very quick capture with Starnet applied on just the combined SHO (though I get the same result if I apply starnet separately to the masters). I am wondering if atmospherics are playing a part as well as I had to image lower down (around 30 degrees) to capture the image. The whole thing is quite blotchy but only after Starnet. Anyone know how to get rid of this beyond a clone stamp job? Perhaps I might ditch starnet for this particular process and add in the RGB stars later and use the usual morphological transform tool.

Workspace02.jpg



#4 Madratter

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Posted 25 May 2020 - 09:47 AM

Starnet leaves artifacts just like every other star removal process I have ever tried. It is much better than some and definitely has ease of use as one of its virtues.

 

But perfect it isn't.



#5 Der_Pit

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Posted 25 May 2020 - 04:48 PM

Yes, for bright/extended stars I also get those artifacts.  You just need to brush up the result of StarNet, using filters like 'Heal Selection' (that's what I use in the GIMP).  Small price to pay for otherwise astounding results in star removal....




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