Revisited NGC7000 - The North American Nebula

[Grant93]

Hi all,

Back again at the NAN, but this time with the modified camera, unlike my one back in summer which was a unmodded one. I plan on adding to this on my next clear night, but I am pretty happy with the results as is, but I do want better SNR. Really struggled to process this with the massive amount of stars overtaking the image, some advice would be very welcome on how to work around the stars, reducing as much as possible to help the nebulosity pop a bit more. Will add the TIFF see if anyone else wants to give it a go at processing

Anyhow, heres just over 3 hours of the NAN and Pelican. Under about a half moon, although so far from the target I dont think it even effected it, could still see a washed out milky way for the majority of the early night at the Zenith.

3 Hours @ 90 Second exposures - Manually dithered every 5ish frames (Its good I dont get bored under a clear night sky)

25 Flats and Bias

Processed in StarTools mainly with some tweaks in Gimp.

Samyang 135mm

Modded 600D

SGP

Regards,

Grant

 

 

600D NA Nebula.TIF

[alacant]

1 hour ago, Grant93 said:

Processed in StarTools

Lovely data and a nice process.

Maybe leave a more room for the fainter stuff via the AutoDevs? This is with -very close to default- settings- on v1.8.512 under Ubuntu:

 

 

Edited September 28, 2021 by alacant

[Grant93]

Love the color of the nebulosity and stars.

Can you expand on the leaving more room for the fainter stuff? Not sure I understand.

Thank you 😃

Regards

Grant

[alacant]

1 hour ago, Grant93 said:

fainter stuff

Not sure what st modules you used nor what you did in GIMP but here are a few general points for st and faint nebulosity.

On the second and any subsequent AutoDevs, try including a more representative ROI. Experiment with different ROIs looking at the effect of each. For example, try part of the nebula, then an area of star field. Try a saturated star with and without background... The best way to get the hang of it is to try it. It only takes a few seconds and you see the results instantly.

In this shot I think it important to sample faint nebulosity as well as part of that dense star field, otherwise as you note, the stars take over.

Another good indication of whether you're losing data is to have a look at the transition between nebula and background. Don't allow the latter to go too dark with too abrupt a gradient. 

Don't worry if you don't get it right first time as the beauty of st is that you can redo development as and when you like.

 

Edited September 28, 2021 by alacant

[Stuf1978]

I had a quick go with your data in Siril and Photoshop, it's nice data with some nice detail especially in the dark dusy areas  

The sheer number of stars in this area is always going to give you problems and it's really hard to tease out any of the finer details without blowing out all the stars. Anyway I performed a quick photometric colour calibration in Siril and used the autostretch function. The image was then transferred to Photoshop where I used selective colour to single out the nebulosity and performed a slight curve adjustment to bring out a little more detail. I then used the astronomy tools action set to make stars smaller and enhance the DSO. Then it was just a few tweaks in camera raw to vibrance and saturation. 

 

[Grant93]

12 hours ago, alacant said:

Not sure what st modules you used nor what you did in GIMP but here are a few general points for st and faint nebulosity.

On the second and any subsequent AutoDevs, try including a more representative ROI. Experiment with different ROIs looking at the effect of each. For example, try part of the nebula, then an area of star field. Try a saturated star with and without background... The best way to get the hang of it is to try it. It only takes a few seconds and you see the results instantly.

In this shot I think it important to sample faint nebulosity as well as part of that dense star field, otherwise as you note, the stars take over.

Another good indication of whether you're losing data is to have a look at the transition between nebula and background. Don't allow the latter to go too dark with too abrupt a gradient. 

Don't worry if you don't get it right first time as the beauty of st is that you can redo development as and when you like.

 

Thanks for that, will revisit this post when I come to processing again

11 hours ago, Stuf1978 said:

I had a quick go with your data in Siril and Photoshop, it's nice data with some nice detail especially in the dark dusy areas  

The sheer number of stars in this area is always going to give you problems and it's really hard to tease out any of the finer details without blowing out all the stars. Anyway I performed a quick photometric colour calibration in Siril and used the autostretch function. The image was then transferred to Photoshop where I used selective colour to single out the nebulosity and performed a slight curve adjustment to bring out a little more detail. I then used the astronomy tools action set to make stars smaller and enhance the DSO. Then it was just a few tweaks in camera raw to vibrance and saturation.

Nice process! Thank you, always nice to see what other people and software do with the same image

[Clarkey]

Just had a quick go at this. I tried to keep as much of the red nebulosity across the field. Maybe a little too colourful...

This was a merger of a de-starred version (starnet++) and the original, some stretching and run through Astroflat pro add-in. Good data to process.

[Grant93]

2 hours ago, Clarkey said:

Just had a quick go at this. I tried to keep as much of the red nebulosity across the field. Maybe a little too colourful...

This was a merger of a de-starred version (starnet++) and the original, some stretching and run through Astroflat pro add-in. Good data to process.

Nice process, I too love to try and get a nice darker red, but struggle not to saturate the rest of the picture also! As you will see in my further efforts following

But yeah did a couple more efforts, the dark red one is probably too overprocessed, but I like saturated reds, but struggle to not saturate the background aswell as the stars. So its a struggle to keep it from looking overprocessed.

The other one I love the color of the stars, but want a deeper red in the nebulosity but can't achieve it without saturating the stars too.. But atleast it doesnt look overprocessed, to me..

Let me know what you think

[alacant]

17 minutes ago, Grant93 said:

can't achieve it without saturating the stars too

AutoDev-decon-shrink the stars where you want them, then use Entropy to boost just the Ha channel.

Try loading the red into NBAccent?

Like the first one. Especially the stars.

Cheers

Edited September 29, 2021 by alacant

[Grant93]

50 minutes ago, alacant said:

AutoDev-decon-shrink the stars where you want them, then use Entropy to boost just the Ha channel.

Try loading the red into NBAccent?

Like the first one. Especially the stars.

Cheers

Wanting to try this NBAccent after reading about it, but can't find it on there 😕

[alacant]

1 hour ago, Grant93 said:

can't find it

You need the bleeding edge version. Don't worry. It's very stable already.

If you can get some frames with a say a bi colour or UHC filter, so much the better.