M81 Processing Request

I more or less followed the same steps as you.  Instead of DBE I used the gradient correction process. I did correct only BlurX before SPCC, and then normal BlurX after SPCC. I took the stars out before any stretching, and used histogram transformation to stretch the stars, but GHS for the starless image. I apparently didn't make a very good mask because when upping the blue saturation, it did in the background too. That's something I would fix if it was my image but not when doing a quick one like this.

For anyone else looking to do SPCC, when doing image solver enter 450 for the focal length and it should solve.

Okay, here it is:

What I did:

- Autostretch
- Background Extraction
- Starnet

Starless:
- GHS stretch
- Asinh black point increase
- Normal black point increase
- More stretching
- Reds and oranges saturation increase

Moved Starless into Photoshop Camera Raw:
- Color noise reduction
- Highlights reduction

Moved Starless into Astrosharp:
- AstroClean (noise reduction)

Moved Starless back into Siril:
- Asinh black point increase

Moved Starless back into Photoshop:
- Orange color desaturation

Added Stars image into Photoshop
- Stars image superimposed onto Starless using Lighten (both layers still separated)
- Stars stretched
- Stars on galaxy blurred a little
- Stars saturated a little
- Cigar galaxy selected and saturated reds on it

- Image layers flattened
- Image cropped
- Image exported


And I think that's what I did; this is all from memory, so I'm not 100% sure.

EDIT: I also wasn't able to pull out any blues from either galaxy, and I like Quinn's version better.

18 hrs. From Bortle 8 skies. Needed some noise reduction  

Okay, here it is:

What I did:

- Autostretch
- Background Extraction
- Starnet

Starless:
- GHS stretch
- Asinh black point increase
- Normal black point increase
- More stretching
- Reds and oranges saturation increase

Moved Starless into Photoshop Camera Raw:
- Color noise reduction
- Highlights reduction

Moved Starless into Astrosharp:
- AstroClean (noise reduction)

Moved Starless back into Siril:
- Asinh black point increase

Moved Starless back into Photoshop:
- Orange color desaturation

Added Stars image into Photoshop
- Stars image superimposed onto Starless using Lighten (both layers still separated)
- Stars stretched
- Stars on galaxy blurred a little
- Stars saturated a little
- Cigar galaxy selected and saturated reds on it

- Image layers flattened
- Image cropped
- Image exported


And I think that's what I did; this is all from memory, so I'm not 100% sure.

EDIT: I also wasn't able to pull out any blues from either galaxy, and I like Quinn's version better.

Beautiful edit, thanks for taking the time to share. 

I actually am surprised you decided to keep good ol M82 in the final image, as I hadn't initially framed my subs with the intention of focusing on M82 but it's neat to see it in there!

Good to see I'm not the only one that removes the orange tones from my images. Depending on which part of the sky my images come from, I've always had to use camera raw to play with the colors to try and get rid of light pollution orange cast. 

I still am on the fence weather I like noise reduction better in PI or PS. 

It's also interesting you use Lighten blend mode to add stars back onto starless, I used to use this method but recently before moving over to PI would use screen as I believed it looked a little more natural and the star edges weren't abruptly "cut off". 

In the end it's all personal preference. Once again thanks for sharing

Fabian Butkovich:

Quinn Groessl:
I more or less followed the same steps as you.  Instead of DBE I used the gradient correction process. I did correct only BlurX before SPCC, and then normal BlurX after SPCC. I took the stars out before any stretching, and used histogram transformation to stretch the stars, but GHS for the starless image. I apparently didn't make a very good mask because when upping the blue saturation, it did in the background too. That's something I would fix if it was my image but not when doing a quick one like this.

For anyone else looking to do SPCC, when doing image solver enter 450 for the focal length and it should solve.

Excellent edit, I think yours is one of my favorites. I'm curious, is there any advantage over using Gradient Correction process versus DBE? I like that you were able to pull out some of the blue tones and also the center core looks well balanced and not blown out. Thanks for mentioning the masked saturation adjustment, I used to do that in Photoshop before I stared using PI and completely overlooked using that method to prevent adding additional noise or saturation to the sky background. 

Also I'm really curious, why specifically 450 for the FL in SPCC? This image is originally taken at 600mm focal length, that's the number I've been using, is this wrong?

Gradient correction simply because it’s new and easier to use than DBE. I don’t have photoshop, so if it’s easier in there, then I’d say keep doing it in PS. 

As for the focal length, I actually entered 350, but in the process box when it was done it said 450-something. As long as it solves, I would say it doesn’t really matter.

Here is my attempt, thanks for fun practice as I am working this and M81 as well. This was all done in Pixinsight.


Split Channels

For each channel:
Dynamic Crop
Gradient Correction
BlurXterminator

Combine Channels
SPCC
SCNR
StarXterminator
Extract Synthetic L From RGB

RGB:
GHS
NoiseXterminator

L:
GHS
HDR Multiscale Transform Mix with signal mask
Unsharpened Mask with signal mask
Multiscale Linear Transform with signal mask
Combine L, HDR, MLT for sharpened L
Dark Structure Enhance
NoiseXterminator

Final RGB:
LRGB Combination
GHS & Linear stretch for brightness and background
Curves for Color
GHS Stars
Curves for Star Color
PixMath Screen Combine Stars

I did mine on Pix and Ps with Xterminator suite.

I'll take a look later

Dale Penkala:
I'm a person that likes color so I put more color in my image for you than others may have. I used masks to help eliminate over saturating the background of the galaxy. That said I didn't add any color other then what your data provided. I added back your luminance to add the extra color.

Anyway my take on your data.

Dale

Lovely edit! While not as sharp as some of the others, I think you've certainly got the best color rendition in your version. The center core is really crisp with the thin brown band I think it looks really good. Nice work Dale thanks for sharing 👍

I wonder if I could make a collaborative post where I blend everyone's together lol 
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