I give up. Here's 40 hours of data, can you crack this one?

[astro_john_palmer]

On 29/06/2020 at 22:58, gorann said:

Nice nebula but never forget to watch out for what you do to the stars while processing. Protect them with masks when you stretch the data. Ideally their cores should not be bigger (blown out) than in the unstretched image.

Thanks very much for the tip Gorann, I will have another go and try to improve.

[astro_john_palmer]

On 29/06/2020 at 22:58, gorann said:

Nice nebula but never forget to watch out for what you do to the stars while processing. Protect them with masks when you stretch the data. Ideally their cores should not be bigger (blown out) than in the unstretched image.

Hi Gorann,

I had another go, think I did a better job of protecting the stars this time, and also actually prefer the outcome overall.

On 30/06/2020 at 16:31, ultranova said:

Cracking image DataLord, well done,

I think Beauty is going to be in the eye of the beholder on this one.

Paul

I agree, so many different ways to edit and such a variety of outcomes depending on preferences.

[Xiga]

On 24/06/2020 at 18:37, Datalord said:

I've struggled with the crescent for a year. Last year I had a lot of data on it, but never achieved a result I was happy with. This year I decided to add some more O3 to improve oxygen and utilize my better processing skills.

Didn't work. I just can't get the colours right. I only have Ha and O3, but I have about 20 hours of data on each. The subs look fine to me stacked and deconvolved, but I fail.

If you try it, please post your result and what you did to achieve it. I would appreciate it immensely.

Here's the result from last year:

Here's a link to the linear stacked, DBE's, deconvolved subs:

https://www.dropbox.com/sh/swyq2bzkjggne3y/AADehllXIJjLCKAOJDhKNAKMa?dl=0

Hi mate

Thanks for sharing! The data is good, very good in fact. I couldn't resist having a pop myself. 

My rough workflow (if i can remember fully, i had a few craft beers to keep me hydrated throughout 😋 ) was as follows:

1. Gradient reduction on the Oiii (using APP). I didn't bother doing it on the Ha. If there is a gradient in the Ha, i couldn't see it.

2. DDP Stretch and crop both stacks. 

3. Topaz DeNoise AI ran on both stacks. Some cleanup in PS using the Spot Healing Brush. 

4. Run starnet on both the DeNoised Ha and Oiii. Then stretch the Oiii a bit further. 

5. Add Ha to Red, Oiii to Blue, then run Carboni's 'Synthesize Green Channel' action, all in PS. This formed the basis for the nebula itself.

From here on it's too hard to list exactly what i did (i blame the 8% IPA, lol). It was basically a combination of using the Denoised Ha image as Luminance for the stars, along with a HOO version used for star colour only, plus some cosmetic correction on some of the stars on the inside of the nebula. I also used a lesser-stretched Ha layer as Luminance for some of the really big stars, and then at the very end i did a pass of star reduction in Images Plus.

It was a challenging image to process, but lots of fun too, so thanks again for sharing it. 

Edited July 4, 2020 by Xiga

[TerryMcK]

5 hours ago, Xiga said:

Hi mate

Thanks for sharing! The data is good, very good in fact. I couldn't resist having a pop myself. 

My rough workflow (if i can remember fully, i had a few craft beers to keep me hydrated throughout 😋 ) was as follows:

1. Gradient reduction on the Oiii (using APP). I didn't bother doing it on the Ha. If there is a gradient in the Ha, i couldn't see it.

2. DDP Stretch and crop both stacks. 

3. Topaz DeNoise AI ran on both stacks. Some cleanup in PS using the Spot Healing Brush. 

4. Run starnet on both the DeNoised Ha and Oiii. Then stretch the Oiii a bit further. 

5. Add Ha to Red, Oiii to Blue, then run Carboni's 'Synthesize Green Channel' action, all in PS. This formed the basis for the nebula itself.

From here on it's too hard to list exactly what i did (i blame the 8% IPA, lol). It was basically a combination of using the Denoised Ha image as Luminance for the stars, along with a HOO version used for star colour only, plus some cosmetic correction on some of the stars on the inside of the nebula. I also used a lesser-stretched Ha layer as Luminance for some of the really big stars, and then at the very end i did a pass of star reduction in Images Plus.

It was a challenging image to process, but lots of fun too, so thanks again for sharing it. 

A great description of your workflow Ciarán 

[Datalord]

21 hours ago, Xiga said:

It was a challenging image to process, but lots of fun too, so thanks again for sharing it. 

That's a beautiful and delicate image you managed to get out of it. Really well done! 

[etunar]

Thanks for sharing your data Datalord. Not having worked with proper mono stacks before I thought I'd have a go.

- Used the base stacks and stretched in photoshop.

- Created starless copies of both ha and O3 using starnet

- further minor stretch on the starless copies.

- combined the starless copies into HAOO.

- used the copy of Ha that was stretched at the beginning as a luminiosity layer and blended with the colour image.

 

It was interesting to work with - that blue quickly disappears under red despite looking bright in mono images. Very clean data to work with!

[ollypenrice]

I'll never be able to download those files with the current internet situation here but the initial image seemed oversharpened, to my eye, and I was instantly suspicious of deconvolution. Shock horror but I don't use it at all. 

I think Ciaran has nailed it, with a result that looks fluffy and yet has all the detail crystal clear.

Olly

[Datalord]

2 hours ago, ollypenrice said:

I think Ciaran has nailed it, with a result that looks fluffy and yet has all the detail crystal clear.

Agree, he nailed it. I'll have to try to do that myself.

[wimvb]

FWIW, here's my stab at the data. I'm not at all familiar with NB bicolour processing and tried various palettes. In the end, simple HOO with SCNR green, won.

All messed up in PixInsight, as usual.

(click on the image for a larger version)

[gorann]

Had another go at it this rainy day and I think it improved from my previous versions, but maybe I should have had some 8% IPA like Ciaran when he processed his excellent version🍺

[AbsolutelyN]

10 minutes ago, gorann said:

Had another go at it this rainy day and I think it improved from my previous versions, but maybe I should have had some 8% IPA like Ciaran when he processed his excellent version🍺

Looks amazing! 

[Datalord]

2 minutes ago, AbsolutelyN said:

Looks amazing! 

Agree!

Looks like this data has been a sufficient challenge for everyone. It's really interesting to see just how different results we all get from the exact same starting point.

[gorann]

56 minutes ago, Datalord said:

Agree!

Looks like this data has been a sufficient challenge for everyone. It's really interesting to see just how different results we all get from the exact same starting point.

If I started off from scratch I am sure I would end up with something different from this first attempt (now in saved version 19 on my HD) - almost tempted to try. I do have some initial workflow but soon it drifts into trial and error and inspiration / desperation🥴.

[silentrunning]

I found this a tricky object to process as well.

If you do a Google search for NGC6888 thousands of images come back very few of which appear 'right' to me or give me something to aim for. Strange object.

 

[gorann]

3 hours ago, silentrunning said:

I found this a tricky object to process as well.

If you do a Google search for NGC6888 thousands of images come back very few of which appear 'right' to me or give me something to aim for. Strange object.

 

Yes, very tricky. I love the blue Oiii signal but when I try to bring it out it messes up the nice Ha structure in the nebula. It just comes down to negotiating one over the other and to find an ok mix. So far I think Ciaran has come closest to a good mix. Here is my stretched version of the Oiii data - looks nice (except for the gradients in the edges), but it is just so difficukt to mix nicely with the Ha. Clearly it is a nicely structured shell of Oiii around the nebula.

Edited July 20, 2020 by gorann