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The problem with the data upload limit for attachments has been fixed. I have restored it to 30MegaBytes. A recent forum software upgrade was responsible for the changed limit. Please accept my apologies for missing this when upgrading the forum sofware, Mabula.

Workflow for STC dual narrowband filter  

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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
09/07/2018 10:54 pm  

Hi Mabula,

I have started to use this filter in combination with my ASI071MC color camera: 

Astro Duo-Narrowband Filter

The question is now how to process these images correctly. Practically I have only red and blue, but APP tries to restore a true RGB color balance I suppose. 

Can you give a hint how should I process the images to get the expected bicolor result. These are my attempts so far ( I am not really satisfied yet):

https://www.astrobin.com/351999/B/?nc=user

https://www.astrobin.com/353634/?nc=user

https://www.astrobin.com/352004/?nc=user

https://www.astrobin.com/354936/?nc=user

Clear skies!

Janos

EDIT by Mabula: inserted URLs to the images, the forum will automatically embed these 😉

This topic was modified 1 year ago by Mabula Haverkamp - Admin

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(@kross)
Brown Dwarf Customer
Joined: 1 year ago
Posts: 8
10/07/2018 10:19 pm  

I've been eyeing those filters myself.  In APP, in the "Combine RGB" tool, when you add the final integration to the tool, it will iterate through all 3 channels of the file and ask what you want to do with them.  (No need to separate the 3 channels into individual files in Photoshop).  So for channel 1, you could assign it to Halpha, channel 2 to something unused, like SII.  Then channel 3 to OIII.  (Or did I get channel 2 and 3 backwards?)  Then you can combine the Halpha and OIII in the tool just like you would from separate files.

I haven't tried this, but it should work.  If you get good results, I may pull the trigger and buy one of the filters. 🙂

-- Kevin

 


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(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2106
12/07/2018 10:51 pm  
Posted by: Janos

Hi Mabula,

I have started to use this filter in combination with my ASI071MC color camera: 

Astro Duo-Narrowband Filter

The question is now how to process these images correctly. Practically I have only red and blue, but APP tries to restore a true RGB color balance I suppose. 

Can you give a hint how should I process the images to get the expected bicolor result. These are my attempts so far ( I am not really satisfied yet):

https://www.astrobin.com/351999/B/?nc=user

https://www.astrobin.com/353634/?nc=user

https://www.astrobin.com/352004/?nc=user

https://www.astrobin.com/354936/?nc=user

Clear skies!

Janos

 

Dear Janos @jarbi58,

This is an interesting situation ;-).

So, the filter has transmission for H-alpha (deep Red) and OIII (Blue/Green):

Image from

Astro Duo-Narrowband Filter

:

Yes, by default, APP will debayer with the Adaptive Airy Disc algorithm. This algortihm needs good signal in the green channel to be most effective. So for your filter, I think we might need to choose another algorithm or even create a new one. If there is enough OIII signal in the data, the Adatpive Airy Disc will still work fine, but for objects with little to no OIII, it will not. (Then simply use the H-alpha debayer algortihm for H-alpha output)

For just RGB output, choose the bilinear interpolation and check if the results are different if you look at the colors and star edges.. That is very interesting to know for me.

As you probably know, I have created narrowband debayer algorithms. These will create monochrome h-alpha output of, for instance, H-alpha data shot with an OSC/DSLR directly.

For your filter, I might be able to implement a specialised debayer algorithm as well. Perhaps with the option to create monochrome output(like a luminance) or a bi-color in a balanced way.

If you can share some of your frames shot with the filter, I will be happy to work on this for the next release 😉

Regarding your images, they do look good, but probably H-alpha is overpowering the OIII signal quite a bit, which is normal. Have you tried the RGB Combine tool and boosted the blue channel with respect to the red channel?

NGC7000 by Janos Barabas @jarbi58:

Kind regards,

Mabula

 

This post was modified 1 year ago 3 times by Mabula Haverkamp - Admin

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2106
12/07/2018 11:09 pm  
Posted by: kross

I've been eyeing those filters myself.  In APP, in the "Combine RGB" tool, when you add the final integration to the tool, it will iterate through all 3 channels of the file and ask what you want to do with them.  (No need to separate the 3 channels into individual files in Photoshop).  So for channel 1, you could assign it to Halpha, channel 2 to something unused, like SII.  Then channel 3 to OIII.  (Or did I get channel 2 and 3 backwards?)  Then you can combine the Halpha and OIII in the tool just like you would from separate files.

I haven't tried this, but it should work.  If you get good results, I may pull the trigger and buy one of the filters. 🙂

-- Kevin

 

Thank you @kross for sharing your thoughts on this 😉

I agree, the balance from the H-alpha and OIII signals could be found to create a nice Bi-Color, using the RGB combine tool. I would assign H-alpha to Red, and OIII to both green and blue. Then increase the multiplier for the OIII data, probably somewhere to 2-4. That should already give a more balanced results I suspect.

A more fine tuned results would be to mix it up a little bit more, but perhaps I can demonstrate that if Janos @jarbi58 sends me some of his data.

Cheers,

Mabula

 

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@kross)
Brown Dwarf Customer
Joined: 1 year ago
Posts: 8
13/07/2018 3:37 am  

I'm using a modified DSLR, and would like to start narrowband imaging. The dual narrowband filter looks like an inexpensive way to get started.  APP is also my image processing program of choice, so I'm anxiously awaiting the results of this, to make a decision if I should spend the money on the dual filter, or just put that money into saving for a "real" setup (mono CMOS astro camera, filters, filter wheel, etc.).

 


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
13/07/2018 9:18 am  

Hi Mabula and other,

Thanks for your replies and ideas so far, please feel free to experiment with my NGC7000 data:  https://drive.google.com/open?id=1XIVTdFaAwvRSMW2Q6ZjYJ9HJzGF9G0Ez

I will certainly do further tests with the suggestes workflows and hopefully I can shoot more images as well 😉

Cheers,

Janos

 

 


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
13/07/2018 9:30 am  

Hi,

Some more data to experiment with from the SH2-101:  https://drive.google.com/open?id=1hcdOl6ZorYoSM2X1df97Ux-PLbnRPvSS

This one has more OIII data normally, 

 

Cheers,

Janos

 


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
13/07/2018 12:08 pm  

Hi Mabula,

I have reprocessed Sh2-101 with bilinear interpolation in APP. The result was initially too blue and green, so I needed to tune these channels down. After that I achieved a better color balance I believe, see hier:  https://www.astrobin.com/354936/B/

Cheers,

Janos

 

 


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
15/07/2018 12:50 pm  

Just to share the result of my last session yesterday evening: the Veil nebula complex with the STC filter. During processing I just kept default for the debayering algorithm, 

https://www.astrobin.com/355984/?nc=user

Cheers,

Janos

 

This post was modified 1 year ago by Mabula Haverkamp - Admin

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(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2106
19/07/2018 9:29 pm  
Posted by: Janos

Just to share the result of my last session yesterday evening: the Veil nebula complex with the STC filter. During processing I just kept default for the debayering algorithm, 

https://www.astrobin.com/355984/?nc=user

Cheers,

Janos

 

Hi Janos @jarbi58,

This looks very nice indeed 😉

I haven't had time yet, to look at your data, but I will in the upcoming days 😉

Mabula

This post was modified 1 year ago by Mabula Haverkamp - Admin

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
22/07/2018 4:43 pm  
Posted by: Mabula Haverkamp - Admin
Posted by: Janos

Just to share the result of my last session yesterday evening: the Veil nebula complex with the STC filter. During processing I just kept default for the debayering algorithm, 

https://www.astrobin.com/355984/?nc=user

Cheers,

Janos

 

Hi Janos @jarbi58,

This looks very nice indeed 😉

I haven't had time yet, to look at your data, but I will in the upcoming days 😉

Mabula

Thanks Mabula,

I'm looking forward to read your findings 😉

Cheers,

Janos

 

 


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(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2106
28/09/2018 12:51 pm  

Hi Janos @jarbi58,

It took some time, but I am now working an a special debayer option in APP for STC DUO filter data. I downloaded your NGC7000  and SH2-101 data and I received more data from Anne van Houwelingen @annehouw as well.

I'll keep you updated on my progress 😉

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
28/09/2018 1:03 pm  
Posted by: Mabula Haverkamp - Admin

Hi Janos @jarbi58,

It took some time, but I am now working an a special debayer option in APP for STC DUO filter data. I downloaded your NGC7000  and SH2-101 data and I received more data from Anne van Houwelingen @annehouw as well.

I'll keep you updated on my progress 😉

Mabula

Thanks Mabula,

I am looking forward to see the new option !


ReplyQuote
(@mabula-admin)
Quasar Admin
Joined: 2 years ago
Posts: 2106
01/10/2018 1:33 pm  

Hi Janos @jarbi58, Kross @kross and Anne @annehouw ,

I have implemented full support for these kind of filters, so-called Multiple Narrowband Filters.

I will soon release APP 1.068 with these new debayer algortihms. You can find all details here:

https://www.astropixelprocessor.com/community/release-information/astro-pixel-processor-1-068-preparing-next-release/

Thank you very much for providing me with test data 😉

Kind regards,

Mabula

Main developer of Astro Pixel Processor and owner of Aries Productions


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(@adrienl)
Molecular Cloud Customer
Joined: 9 months ago
Posts: 3
10/11/2018 1:51 pm  

Hello

reviving this thread as I have the same combo as you Janos (ASI071 and STC duo narrowband filter). New to APP, so it is surely a dumb question, but try as I may, I only get monochrome images (B&W), whatever debayer option I use (H-alpha OIII colour, or separate H-alpha and OIII extractions + RGB combine tool).

I have tried pattern option "supported" and RGGB (which is what I was using in DSS), not to avail. So I am a bit left scratching my head here. If one of you guys can point me in the right direction, it would be cool !

Thanks and CS

Adrien


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
10/11/2018 8:35 pm  
Posted by: AdrienL

Hello

reviving this thread as I have the same combo as you Janos (ASI071 and STC duo narrowband filter). New to APP, so it is surely a dumb question, but try as I may, I only get monochrome images (B&W), whatever debayer option I use (H-alpha OIII colour, or separate H-alpha and OIII extractions + RGB combine tool).

I have tried pattern option "supported" and RGGB (which is what I was using in DSS), not to avail. So I am a bit left scratching my head here. If one of you guys can point me in the right direction, it would be cool !

Thanks and CS

Adrien

Hi Adrien,

You are maybe just one click away from the solution :-). When you select RGGB, you need to tick also the checkbox "force Bayer CFA". I hope this helps.

One more question just to be sure: you have shot all frames in RAW format I believe,

 

CS,

Janos

 


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(@jarbi58)
Main Sequence Star Customer
Joined: 2 years ago
Posts: 30
10/11/2018 8:47 pm  

Adrien,

I forgot to mention: if you have the latest version of APP, choose debayering option "HA-OIII color", pattern "RGGB" and activate checkbox "force Bayer CFA" to get the best results with this filter,

 

CS,

Janos

 


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(@adrienl)
Molecular Cloud Customer
Joined: 9 months ago
Posts: 3
10/11/2018 9:13 pm  

Thanks so much Janos for the quick turn around ! I'll give it a go and report back.

kind regards

Adrien


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(@rowland-f-archer-jr)
Red Giant Customer
Joined: 2 years ago
Posts: 70
11/11/2018 12:15 pm  

I also have the STC dual NB filter.  One other trap to avoid - if you forget to check "Force Bayer CFA" the first time you run APP, it may produce master calibration frames (darks, flats, bias, BPM) that are not de-Bayered.  You should not use those master frames with de-Bayered light frames.   Delete them if you have them in your file list, and create new master calibration frames that are also de-Bayered with the "Force Bayer CFA" box checked.

Cheers,

Rowland


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(@adrienl)
Molecular Cloud Customer
Joined: 9 months ago
Posts: 3
11/11/2018 4:05 pm  

thanks Roland and Janos for the good tips. It did work!

I'll try next to do some extracts in Halpha and Oiii separetely and combine them to see how that compares. Cheers

Adrien


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