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Backyard Space Dude

NGC6888 - The Crescent Nebula in HOO

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Hi everyone! Managed to capture 9hrs Ha and 11hrs Oiii (7nm) on this one.


SW 80ED DS-Pro
ZWO ASI1600MM Pro
SW NEQ6 Pro
ZWO ASIAir Pro
SiriL
StarNet++
Adobe Photoshop CC

Thanks for looking!

50348289211_c7f76c263b_o.jpg

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Just zoomed in on the Crescent and the detail is amazing. Excellent image.

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Wow, about as good as it gets on this Nebula

striking detail and colors, the O3 really makes this pop, almost 3d,

well done 

Paul

 

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Stunning, as good as any I have ever seen of this target.

Alan

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Very nice...   and you've also just got the top of the Soap Bubble at bottom middle

Dave

Edited by Laurin Dave
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That's an absolutely incredible image! Well done. Best I've seen of the crescent 

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Awesome job.  It is the best that I can recall seeing of this nebula.  

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Wow, I honestly wasn't expecting this response! Thank you all so very much for your kind words. 

7 hours ago, steppenwolf said:

Lovely 3D looking image - really like this!

Thank you Steve, it all started with your book so I'm a little star-struck knowing you liked my image!

 

4 hours ago, Laurin Dave said:

Very nice...   and you've also just got the top of the Soap Bubble at bottom middle

Dave

Yes, haha I totally forgot it was there until I started post-processing, then was gutted that I didn't frame it better! 

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Very very impressive! And with an ED80 :icon_salut:

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A very rare beautiful photo. Rich of details and shadows. Excellent postprocessing.

Would you mind share more details on the imaging and postprocessing?

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1 hour ago, GiorgioF said:

A very rare beautiful photo. Rich of details and shadows. Excellent postprocessing.

Would you mind share more details on the imaging and postprocessing?

Thank you! This is the basic process as I remember it:

Captured data over 5 nights in September from my back garden in a Bortle 4 zone (borderline 5).

Fully calibrated and combined in SiriL,

Simple stretch in Photoshop,

Exported and run through StarNet++,

Each channel into Photoshop for stretching, spot healing any star residue, curves, noise reduction (combination of Topaz Labs DeNoise and Astronomy Tools), smart sharpening,

Combination of the HOO palette,

Some changes to hue and saturation, further sharpening of the Oiii using masks,

Reduced the star size separately (still haven't fully got the hang of this as you can see some really bad artefacts when zoomed in) before adding them in and reducing them further to taste,

Spend hours pondering over what to do next, sleep on it, post it the next morning!

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I cant stop looking at this, its mental! 😊

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On 17/09/2020 at 22:51, Backyard Space Dude said:

Thank you! This is the basic process as I remember it:

Captured data over 5 nights in September from my back garden in a Bortle 4 zone (borderline 5).

Fully calibrated and combined in SiriL,

Simple stretch in Photoshop,

Exported and run through StarNet++,

Each channel into Photoshop for stretching, spot healing any star residue, curves, noise reduction (combination of Topaz Labs DeNoise and Astronomy Tools), smart sharpening,

Combination of the HOO palette,

Some changes to hue and saturation, further sharpening of the Oiii using masks,

Reduced the star size separately (still haven't fully got the hang of this as you can see some really bad artefacts when zoomed in) before adding them in and reducing them further to taste,

Spend hours pondering over what to do next, sleep on it, post it the next morning!

Many thanks! What about the imaging? I mean gain, time of the single light? I apologize for these questions but I'm used to compare with h my usual data and try to understand where I can improve

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On 18/09/2020 at 22:17, GiorgioF said:

Many thanks! What about the imaging? I mean gain, time of the single light? I apologize for these questions but I'm used to compare with h my usual data and try to understand where I can improve

No problem at all! Gain 139, temp -20. 600s exposures. 

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At first glance, its pretty good! Especially the crescent.

However :)  (lol) being the pixel peeper I am, ive had a real close look at it and maybe there is something up with the way the image has been saved off because there is quite a lot of pixelisation going on in the surrounding neubulosity:

Capture4.JPG.08b486d72dfc2fc27ddd8727e6c3870e.JPG

Probably an easy fix, just have a fiddle with the export settings or try a .png file to see if that makes any difference. If its present in the .tiff file, it may be caused by a noise reduction routine somewhere along the processing workflow.

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On 25/09/2020 at 23:46, Uranium235 said:

At first glance, its pretty good! Especially the crescent.

However :)  (lol) being the pixel peeper I am, ive had a real close look at it and maybe there is something up with the way the image has been saved off because there is quite a lot of pixelisation going on in the surrounding neubulosity:

Capture4.JPG.08b486d72dfc2fc27ddd8727e6c3870e.JPG

Probably an easy fix, just have a fiddle with the export settings or try a .png file to see if that makes any difference. If its present in the .tiff file, it may be caused by a noise reduction routine somewhere along the processing workflow.

Good spot! I’m very aware of the weird shaped squiggly stars, I can’t figure out a good way of reducing the stars either before or after adding them back in to the starless layer. I did use some fairly heavy noise reduction with Topaz labs and photoshop so maybe that’s where the pixelation is happening. I’m fairly sure I uploaded the tiff to Flickr and then shared from there to here, so perhaps that has something to do with it, too? Though the original doesn’t look great either haha

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Squiggly stars aside, this is my favourite image of this nebula I have seen. 
 The clarity of the crescent is awesome against that sea of Ha. 
Well done. 

Thank you for sharing your hard work. 

Bryan 

 

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11 hours ago, Backyard Space Dude said:

Good spot! I’m very aware of the weird shaped squiggly stars, I can’t figure out a good way of reducing the stars either before or after adding them back in to the starless layer. I did use some fairly heavy noise reduction with Topaz labs and photoshop so maybe that’s where the pixelation is happening. I’m fairly sure I uploaded the tiff to Flickr and then shared from there to here, so perhaps that has something to do with it, too? Though the original doesn’t look great either haha

For NR, I personally use the normal reduce noise filter in Ps set to 7 or 8 strength, with preserve detail at about 85-90%. Then on the final step, its noise ninja at a very low setting (Strength/Smoothness set to 3 or 4) - and sometimes selectively apply it (using a layer mask). That avoids processing artifacts or the "vaseline" look.

If you want to reduce stars, you can do it in two steps. Firstly by using a layer mask about 3 curves into the stretching - ie: do three curves, then set that image aside as a copy, stretch the original more until the stars are getting too big for comfort (usually another 2-3 curves later), then paste in the one you set aside using a layer mask (so you are compositing the stars only, not the nebulosity). Then, as you are approaching the end of processing, use noels "make stars smaller" action... but only twice at most, otherwise you might get dark halos. Bit hard to explain in plain text...lol, it needs a practical demo.  But either way you need to keep a close eye on the details to avoid those dark halos.

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Superb, I have to say that IMHO this is on a par with the 80 hrs of IKI Observatory data on the this object that folks have recently been poring over on this forum. 
 

You have restored my faith in UK skies. 👍

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