Trying to beat Luminar 4 result for an astro pic

Folks,

Brand new user at Pixls.us, and very new darktable user here.
I’ve been trying to switch over to darktable from other commercial software, and watched dozens of youtube videos, and am just getting the hang of it. My DT processed photos so far are at Quebec 2023 | Flickr, not that it matters.
Last week I took a few milky way pictures as an exercise, so I tried to process them but am not able to get to the result I’d like to get. The raw file is here (CC-BY-SA 4.0):
DSC06267.ARW (81.8 MB)
DSC06267.ARW.xmp (11.2 KB)

The result is somewhat OK, but I would want the milky way to be more pronounced and introduce some color variance to it. The exported jpg looks like this:


I brought the raw file to Luminar 4, with a few minutes and I got this:

Comparing the two results, I can see that DT seems to have better noise removal - the result looks much cleaner, but I think Luminar4 somehow gives more contrast to the milky way and brings out more details in shadows. It was also easier to add a bit magenta by sliders in white balance but I suppose it’s because I still don’t fully understand channel mixer.
I understand the analogy is DT is a manual car with lots of knob to turn, I guess my problem right now is not knowing which knobs to turn.
Any suggestions are welcome.

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Welcome to the forum. :slight_smile:

I had a go with darktable and was able to get a similar result to your Luminar result. Not the same, but relatively speaking a kind of match. Took a while though! I needed a fair bit of experimentation.
I think the Luminar noise reduction is pretty good - I struggled when I tried to prevent the loss of some starry-ness, without making the sky too noisy.
DSC06267.ARW.xmp (11.0 KB)

You can do that with the channel mixer, but when it’s just a matter of white balance the intended approach is to just use the hue and chroma sliders in color calibration.
image
Having said that, I often still prefer the older dt approach, where color calibration is set to bypass, and then use the white balance module itself - there’s usually no real advantage to that though, so here I stuck to the current approach.
But then I added another instance of color calibration and did quite a few channel mixer tweaks.

The next release of DT will have a new module called primaries, which is a channel mixer in disguise - should be good for some things.

Ask if anything needs more explanation! I’m not very good at explaining sometimes… :smile:

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Thanks for your tips :+1: will look into your xmp file!

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Welcome to the forum.

Here’s my attempt. This is quite challenging to bring any amount of detail out of the Milky Way with that much light pollution. *But I’m used to capturing the Milky Way in dark skies tracked with my modded camera…

This is using DT 4.5 dev including the new rgb primaries.

DSC06267.ARW.xmp (19.3 KB)

*One of my recent shots of the MW...

Not trying to detract from your image.

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Thanks Jordan. Yeah was no where near a dark site so just had to make do. I might need to upgrade to v4.5 dev later to test out your edit. Thanks again.

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My quick try.

DSC06267.ARW.xmp (19.5 KB)

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My try:

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DSC06267.ARW.xmp (17.5 KB)

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One of the big problems with astrophotography is deciding on the background colour for the sky. What you see with your eyes see at dusk is very likely less than accurate.

There is colour there in the sky, mostly in the blue/violet area, but your eyes won’t see it as vivid colour. However, the camera does pick it up, so DT can boost and shift that colour as much as you like, even making a milky way scene that is dare-I-say unrealistic.

I guess it depends what you want to do. Me, I’ve fussed over some aurora borealis pictures for 7 years now, through several super DT upgrades and still not happy . . .

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No, not at all. You should just use the daylight preset of your camera and you will get the right sky colors.

https://clarkvision.com/articles/ethics-in-night-photography/

For the milkyway you can do a “contrast equalizer” triplet. One for darken, one for lighten and one for chroma. I can edit the photo later and then you will see how to do it.

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Welcome @Sean_Liu

My version…

DSC06267.ARW.xmp (21.2 KB)

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Thanks Andreas - I guess I need to revisit Clarkvision.com.

It looks like he has reorganised all the material on his website as I previously only saw the section “Color of the Night Sky”. I went through my aurora shots a few years ago based on that article and really didnt like the colours that resulted, but there is a whole lot more technical background on his site so I will take some time to go through it.

I have heard that using 3200K or Tungsten setting for Aurora gives more pleasing color. I am not an expert on this so I am willing to stand corrected. BTW, playing with the RAW file posted in this thread I had determined a white balance around 3383 K as most suitable for my purpose. Daylight was way too warm for my taste with this shot.

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Thanks folks for your kind greetings and your reference edits, I will need to go through the sidecar files and try to learn from each one, likely coming back with more questions :slight_smile:
Just from the jpgs, I can see many of you brought out much more details than I could, so I’ll surely learn from them.
I understand the sky color/white balance for astro can be up to interpretation to some degree so I do get hung up on this.
My intention again was to familiarize myself with DT to get more efficient without resorting to the commercial software, surely I’ll be one step closer.
Again thanks for all your edits and ideas!

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I tried playing with this photo but found it hard to replicate the Luminar result. I suspect Luminar would struggle to replicate the DT result. In my approach I decided to use filmic V5 with preserve chrominance set to no in the hope of bringing out more color. I feel @123sg approach is closest to the Luminar result.
Milky Way
Milky Way.ARW.xmp (17.1 KB)

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Both can be true, as “right” is not the same as “pleasing”. Part of that is cultural or personal taste, just look at the different results in playraws.

And sometimes you want/need the right colour, sometimes you want the most pleasing rendering…

My version…


DSC06267.ARW.xmp (23.4 KB)

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I’ve never done astrophotography before, so I’m not sure what look to aim for. But this is what I managed in a 10-min break from work. I tried to bring out the colours in the Milky Way as much as possible.

DSC06267.ARW.xmp (22.4 KB)

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@europlatus sidecar file please?

Still slowly catching up with the sidecar files and try to understand things :slight_smile:
I am liking:

  1. What @Thomas_Do did with lowpass and diffuse and sharpen that brought out the details and colors of the sky. Also it seemed simple with a single mask.
  2. What @dqpcoxeas did with local contrast and many instances of color balance RGB to bring out the details.
  3. How @jdneumeyer used sigmoid to handle contrast. But since I am still on 4.4.2, not sure how the tint was added yet.
  4. As many has mentioned, @123sg produced the closest result as Luminar, but I have yet to understand properly how he did it.

Again, still slowly going through the xmp’s, but thanks everyone for putting time in it.

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