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North America Nebula from 45N last night

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#1 travishv

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Posted 22 May 2020 - 11:47 PM

Hey all, 

 

I captured this image from a dark sky site last night in Ontario. Thought Id share. 

 

This image is 43x130sec at iso 1600 (i'm sure I should get more data next time). I'm using a Canon SL2 Dslr with SpaceCat51 scope on an ES Exos 2 mount. 

 

I find the number of stars overwhelming. I cant seem to find a way to decrease the intensity of them without making the image look strange. I am using Photoshop for editing. I find the dust and scratches filter takes away too much detail where I don't want to. StarNet does a great job at removing them, but I don't want to remove them all. Any feedback welcome. Fairly new still so be easy! smile.gif

 

Travis 

 

Full Size Jpg

https://drive.google...0AOnRGQBM3o61vo

 

Stacked File

https://drive.google...mqZgkurvwumBC3g

 

 

 

 

Attached Thumbnails

  • North Amera Nebula - small.jpg

Edited by travishv, 23 May 2020 - 12:17 AM.

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#2 maxsid

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Posted 23 May 2020 - 01:14 AM

I had the same problem and even worse since I used a full-spectrum modded DSLR (huge star bloat).

Bought a clip-in IDAS filter and it helped a lot.

 

https://www.cloudyni...ed-idas-filter/



#3 Alen K

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Posted 23 May 2020 - 03:03 PM

You could try a partial stretch of the image, just enough for Starnet++ to work. Then subtract the resulting nebulae-only image from the original to yield a stars-only image. Continue to stretch the nebulae-only image to where you want it. You can likely use the stars-only image as is or stretch it only a bit more. When you sum the stars-only image with the nebulae-only image, the result should be an image with much less prominent stars. 


Edited by Alen K, 23 May 2020 - 03:05 PM.


#4 travishv

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Posted 23 May 2020 - 05:36 PM

That’s a great idea. I’m going to give that a try. Thanks for that.

And definitely a filter could help for next time.

Thanks guys

#5 BQ Octantis

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Posted 23 May 2020 - 08:42 PM

Beautiful colors!

 

There are several ways to reduce stars, but I've found that many produce the strangeness you describe.

 

If you're happy with the starless image from Starnet++, paste it on top of the starry image as a Lighten layer. Then use Curves on the background image to reduce the stars. Since the lighten layer is the nebula, you'll only reduce the stars. Just make sure to edit the curve at the zoom level you intend to present—each zoom level can handle a different amount of star reduction.

 

Here's a crack at your full-size JPEG with this method using Remove Stars in Annie's Astro Actions 7.0 as the top image:

 

(Click for 1440×960)

North America Nebula_reduced.jpg

 

BQ


Edited by BQ Octantis, 23 May 2020 - 08:50 PM.

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#6 sunnyday

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Posted 23 May 2020 - 09:01 PM

very nice this large field.
very successful .
well done and thank you.



#7 travishv

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Posted 24 May 2020 - 12:06 AM

Thanks sunnyday  im happy with the colour too. 

 

I will tinker with the stars a bit.. Thanks for all the great ideas!



#8 Bretw01

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Posted 24 May 2020 - 08:38 AM

Another method for star reduction you can try, I use it a lot.

 

In photoshop duplicate the image and convert to grayscale. Using the magic wand select the background, making sure you are tight to the stars (use shift +left click if needed). Invert and save selection (select/save selection). Go back to the original version, copy it to a new layer. On this layer load the selection you saved. Go to select/modify/expand x 4. Next select/modify/feather x 2.  Go to filter/other/minimum - radius x 1. Deselect to see results, and use the opacity slider to adjust to your liking.

 

Your image before and after using the minimum filter:

 

Untitled-1.gif


Edited by Bretw01, 24 May 2020 - 06:12 PM.



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