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The Wizard Nebula NGC7380 in HOO


paul
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I’m told it is supposed to look like a wizard in a pointed hat and gown with open arms. This image is the result of a 7hr session (4hrs Ha, 3 hrs O3) on a night of full moon, (many subs rejected due to clouds and wind). I’m pretty happy with the result, not so pleased by the halos. Being windy I was limited to 120s subs, PHD2 reported anything from 0.7 to 2 arcsecs rms. 

I’ve combined the signals as R=Ha, G= 0.3*Ha +0.7*O3, B= O3. 

Comments and criticism welcome 🧐

NGC7380_5.thumb.png.fa9e4ce5a2a36554bfd351efd1775f6d.png*Image updated to remove the green cast*

Edited by paul
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22 minutes ago, paul said:

I’m told it is supposed to look like a wizard in a pointed hat and gown with open arms. This image is the result of a 7hr session (4hrs Ha, 3 hrs O3) on a night of full moon, (many subs rejected due to clouds and wind). I’m pretty happy with the result, not so pleased by the halos. Being windy I was limited to 120s subs, PHD2 reported anything from 0.7 to 2 arcsecs rms. 

I’ve combined the signals as R=Ha, G= 0.3*Ha +0.7*O3, B= O3. 

Comments and criticism welcome

 

Interesting colour combination, looks great. Not sure about the green stars though, could be a result of having so much Ha in the green channel.

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6 hours ago, AstronomyUkraine said:

 

Interesting colour combination, looks great. Not sure about the green stars though, could be a result of having so much Ha in the green channel.

I wasn't seeing green until you mentioned it, image now updated!

 

I've pushed the data hard so the there is more processing noise than I'd like. The O3 data was pretty rough. I'll reuse the best of the data for another session on a moonless night and maybe add in some S2.

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10 hours ago, paul said:

I wasn't seeing green until you mentioned it, image now updated!

 

I've pushed the data hard so the there is more processing noise than I'd like. The O3 data was pretty rough. I'll reuse the best of the data for another session on a moonless night and maybe add in some S2.

If you want to remove the halos, try this method by Ron Brecher, it does a great job on small halos. The top image shows the bright halo, the second image is the halo removed. It's not perfect, but a vast improvement. Don't take notice of the background in the second image, that was me messing around trying to remove the large halo.

 

https://astrodoc.ca/wp-content/uploads/2017/01/REMOVING-HALOES-FROM-BRIGHT-STARS.pdf

 

Original.jpg.769fe9fc0a92a94b58bb990533e56255.jpg

 

HaloRemoved.jpg.f714db859fafa16b8663571d78291121.jpg

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2 hours ago, Carastro said:

Nice image Paul, and Brian that halo remover in PI looks great.  Shame there isn't something for photoshop, though I don't often have a halo problem.

 

Carole 

I'm sure there must be some kind of alternative for photoshop Carole. What PI is doing is using reference data from a sub frame from another filter. In this case I was using the Ha data. Then using the clone stamp tool to remove the halo from the OIII data. Basically what PI is doing, is cloning the area around the star from the good data, over the bad data in the OIII frame. I hope that makes sense? 😀

 

Just found an excellent video for halo removal in PS, it is a lot simpler than PI, and the result is excellent. Here is the same data with the halo, but converted to tiff. The top one has the halo, the second has the halo removed. The whole process took two minutes.

 

Halo.thumb.jpg.79170b85c9db0f2a3846a082f4357e92.jpg

 

Hal_Removed.thumb.jpg.e4952bc38814af93f77c0365a39b5fe3.jpg

 

 

Edited by AstronomyUkraine
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On 10/23/2021 at 4:58 PM, paul said:

 

I’m told it is supposed to look like a wizard in a pointed hat and gown with open arms. This image is the result of a 7hr session (4hrs Ha, 3 hrs O3) on a night of full moon, (many subs rejected due to clouds and wind). I’m pretty happy with the result, not so pleased by the halos. Being windy I was limited to 120s subs, PHD2 reported anything from 0.7 to 2 arcsecs rms. 

I’ve combined the signals as R=Ha, G= 0.3*Ha +0.7*O3, B= O3. 

Comments and criticism welcome 🧐

NGC7380_5.thumb.png.fa9e4ce5a2a36554bfd351efd1775f6d.png*Image updated to remove the green cast*

I like it a lot! I can’t criticise because you know my level to me is absolutely amazing! 

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Quote

What PI is doing is using reference data from a sub frame from another filter. In this case I was using the Ha data. Then using the clone stamp tool to remove the halo from the OIII data. Basically what PI is doing, is cloning the area around the star from the good data, over the bad data in the OIII frame. I hope that makes sense? 😀

It does, I did something like that manually once to tame a very bright star,

 

Carole 

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2 hours ago, gabs said:

I like it a lot! I can’t criticise because you know my level to me is absolutely amazing! 

Thanks Gabs, I am my worst critique 🙄. I am impressed with what you have achieved in such a short time.

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14 hours ago, paul said:

Thanks Gabs, I am my worst critique 🙄. I am impressed with what you have achieved in such a short time.

I wasn’t able to do anything

before I found people like you here. 
Your help meant a lot to me!

 

 

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