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  #1  
Old 09-04-2014, 03:05 PM
kosh
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PixInsight DBE tool help please

Hi all,

If anyone has experience using Pixinsight i could use some help with the following images.

I'm trying to use the Dynamic background extraction tool to get rid of the gradient in the left of the image but I can't seem to get it to do much at all!
The Auto extraction does a better job, but still nowhere near the result that I have seen tutorials of. I have included the original, background and the result after DBE. I am using subtraction, normalise, with a radius of 12 and 20 samples per line.
If someone could enlighten me on how i'm stuffing this up i would appreciate it.
Cheers.

PS. forgive the quality of the image itself, I still have lots of work to do on it
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  #2  
Old 09-04-2014, 03:26 PM
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h0ughy (David)
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while that is a gradient it looks more like direct light that got in - har d to remove even for PI
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  #3  
Old 09-04-2014, 04:07 PM
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RickS (Rick)
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This is the best I could do with a quick hack at it... Default sample size increased to 8, Tolerance increased to 1.2, samples auto generated. I saved the process icon and did the same DBE three times. Could almost certainly do better with manual placement of samples and more tuning but, as H0ughy said, it's a tough one.

Cheers,
Rick.
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  #4  
Old 09-04-2014, 07:03 PM
kosh
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Quote:
Originally Posted by h0ughy View Post
while that is a gradient it looks more like direct light that got in - har d to remove even for PI
Yes possibly this one streetlight but I was hoping the fence was cutting most of the direct light out.... It appears not.

Quote:
Originally Posted by RickS View Post
This is the best I could do with a quick hack at it... Default sample size increased to 8, Tolerance increased to 1.2, samples auto generated. I saved the process icon and did the same DBE three times. Could almost certainly do better with manual placement of samples and more tuning but, as H0ughy said, it's a tough one.

Cheers,
Rick.
Thanks Rick. I have tried setting the sample size to 8. I will have a look at changing the tolerance, but I Would be much happier if I could get something like what you have shown.
PIxinsight seems like an awesome package ( I'm evaluating at the moment ) but I definitely need to spend more time with it. Lots to learn...
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  #5  
Old 09-04-2014, 07:11 PM
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RickS (Rick)
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Quote:
Originally Posted by kosh View Post
Thanks Rick. I have tried setting the sample size to 8. I will have a look at changing the tolerance, but I Would be much happier if I could get something like what you have shown.
PIxinsight seems like an awesome package ( I'm evaluating at the moment ) but I definitely need to spend more time with it. Lots to learn...
Definitely a learning curve, Goran, but not insurmountable.

You'll need to tweak the Tolerance value if there is a lot of variation in the background and you get manually placed sample points that are disabled (shown in red) or you auto generate points and don't get good coverage.

It's OK to run DBE multiple times as well.

Good luck!

Cheers,
Rick.
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  #6  
Old 11-04-2014, 09:24 PM
Tony_ (Tony)
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G'day,

Here's my effort with photoshop.
Noise reduced a bit - but loses some detail in the galaxy. Lot's of light gradients in this one - makes it hard. Colour is also hard to balance.
You could improve it more by reducing the star size.

Regards,
Tony.
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  #7  
Old 11-04-2014, 10:42 PM
kosh
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Quote:
Originally Posted by Tony_ View Post
G'day,

Here's my effort with photoshop.
Noise reduced a bit - but loses some detail in the galaxy. Lot's of light gradients in this one - makes it hard. Colour is also hard to balance.
You could improve it more by reducing the star size.

Regards,
Tony.
Thanks tony, I just posted an update version of mine. Feel free to let me know what you think.
Goran.
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  #8  
Old 11-04-2014, 11:39 PM
Tony_ (Tony)
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G'day Goran,

Your new post is a lot better - much more detail in the galaxy. The background is a lot more uniform now too - just need to work on the overall colour balance. I might have to get pixinsight one day - but I've got other software that I don't use properly so it may be just one more.

Regards,
Tony
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