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DBE before or after BN?

Pleiades Astrophoto PixInsight Processing Background Extraction Deep Sky
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Stuart Taylor avatar
Stuart Taylor avatar
I'm trying to learn Pixinsight so I've been watching lots of videos.

Two processes that most people seem to use are dynamic background extraction (which deals with gradients) and background neutralization (not sure what that does).

But they don't always do them in the same order. Some do BN first and others do DBE first.

Does the order matter?

Thanks
Well Written Engaging
Eddie Bagwell avatar
Eddie Bagwell avatar
I'm not an authority on PI and have probably watched a lot of the videos that you have. That being said, I use ABE and DBE first before I use BN based on the consensus of the information that I have collected from videos and vlogs.

I use ABE before LRGB Combination and DBE and BN after LRGB Combination.
Stuart Taylor avatar
Stuart Taylor avatar
I'm not an authority on PI and have probably watched a lot of the videos that you have. That being said, I use ABE and DBE first before I use BN based on the consensus of the information that I have collected from videos and vlogs.

I use ABE before LRGB Combination and BN after LRGB Combination.

Ok, thanks. I've not tried automatic background extraction. Do you need both then?
Sean van Drogen avatar
Sean van Drogen avatar
Have been using this for a while now
andrea tasselli avatar
andrea tasselli avatar
Stuart Taylor:
I'm trying to learn Pixinsight so I've been watching lots of videos.

Two processes that most people seem to use are dynamic background extraction (which deals with gradients) and background neutralization (not sure what that does).

But they don't always do them in the same order. Some do BN first and others do DBE first.

Does the order matter?

Thanks

I do BN first as it allows you to chose the grid points you want on DBE. I don't do "blind" DBE if I can help it unless it's a star field. BN does make the average background level at the minimum level possible and balance out the RGB values of the same.
Eddie Bagwell avatar
Eddie Bagwell avatar
ABE is fast and gives nice results just by using the default values. I use it on the images before combing. It doesn't hurt to use both.
Stuart Taylor avatar
Stuart Taylor avatar
Sean van Drogen:
Have been using this for a while now

Thanks for this. Looks v useful! I should have said I am only imaging with an OSC, so do I use the left hand branch?
Tom Boyd avatar
Tom Boyd avatar
I almost never use BN as part of my standard processing work flow. I DBE first on an unlinked screen stretched version of the raw stack. I then color calibrate using Photometric color calibration tool in PixInsight. I will then, after decon and some noise reduction, often use SCNR to remove any remaining unwanted green. If I use BN, I use it later in the processing workflow when  I am combine datasets such as RGB and Ha and need to neutralize the background post color calibration.
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Marc Ricard avatar
Marc Ricard avatar
You should consider adding MureDenoise at the start of your workflow. It's very good at reducing small scale noise (a.k.a. Poisson noise). It's the first step I apply to my channel masters after integration. Next I crop them and apply DBE. Adam Block has created some excellent videos that explain the intricacies of the various settings of this process. If you're using a mono camera and you collect your color subs sequentially (one color at a time). You should try running DBE on each color master especially if you have to contend with severe light pollution. You can then apply background neutralization with the Photometric Color Calibration process.
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Sean van Drogen avatar
Sean van Drogen avatar
Stuart Taylor:
Sean van Drogen:
Have been using this for a while now

Thanks for this. Looks v useful! I should have said I am only imaging with an OSC, so do I use the left hand branch?

That would be a good question but yes follow left hand side until the end, but most important takeaway always start with some sort of background extraction either DBE or ABE
Stuart Taylor avatar
Stuart Taylor avatar
Sean van Drogen:

That would be a good question but yes follow left hand side until the end, but most important takeaway always start with some sort of background extraction either DBE or ABE

Great. Thanks. So far, my workflow for OSC has been
crop
background neutralization
DBE
SCNR
EZ denoise
EZ soft stretch
then finishing in Photoshop with Astro Flats Pro
Tom Boyd avatar
Tom Boyd avatar
Stuart Taylor:
Sean van Drogen:

That would be a good question but yes follow left hand side until the end, but most important takeaway always start with some sort of background extraction either DBE or ABE

Great. Thanks. So far, my workflow for OSC has been
crop
background neutralization
DBE
SCNR
EZ denoise
EZ soft stretch
then finishing in Photoshop with Astro Flats Pro

You need to add color calibration into your flow. Calibration is done after DBE...