M101 feedback

[ONIKKINEN]

Quick process of the unstretched file in SiriL and photoshop:

Just did photometric colour calibration, stretch, deconvolution, saturation, the usual stuff. In photoshop some layer masked saturation/noise control/sharpness things. Didn't go too far on this one but i think with sharpening and maybe an HDR type process with layer masks there would be more in the image.

I cant advice on how to get results out of startools, because so far i have not had success with it. My tries with Startools always end up looking like they came out of Startools, and i dont think that's a great thing. I find real issue in how the colour module just doesn't seem to get real colour results out no matter what i do, and all the other modules slowly walk the image towards what you got out of it, a posterized and mushy looking image. Some might like the look of getting every bit out of an image but i think it detracts from the image. I see that some people get much better looking results than i can get out of it, so much of this is user error in my end, but i find other software much easier to use for processing.

One issue i found is that the image is 16-bit which is problematic for the faintest detail. I believe that is possibly a part of the issue with the posterized looking edges in Startools. Below is an image of the histogram in siril:

There are gaps in the histogram, meaning that the image has been stretched so far as to no longer fill all the values of a 16bit image. This can lead to abrubt looking edges in faint detail instead of evenly fading away into the background like it should be. Its not super obvious in this example and this is something many people dont bother with, but there is a difference in 32bit and 16bit processing and i think that's reason enough.

Why not try processing in SiriL though? Photometric colour calibration and a histogram transformation and you already have a real colour stretched image that you could then fiddle with in Photoshop or Gimp until the end of time until you get what you like.

Data is great by the way. Really nice capture.

[Pitch Black Skies]

9 hours ago, Jamgood said:

@Pitch Black Skies You sound like you're like me. I always struggle with Galaxies. I find them really difficult to process and I'm never or rarely happy with the result.

I recently upgraded to Astro pixel processor for stacking. You could give the trial version of that a go. It's a bit daunting at first but when you get it, it is a nice powerful tool.

It's just that the guys here are able to produce a nice result with the DSS stacked file. It's more down to the post processing I think.

Edited April 5, 2022 by Pitch Black Skies

[vlaiv]

8 hours ago, ONIKKINEN said:

Quick process of the unstretched file in SiriL and photoshop:

Very nice processing! To my eye, best so far in this thread.

[Pitch Black Skies]

10 hours ago, ONIKKINEN said:

Quick process of the unstretched file in SiriL and photoshop:

Just did photometric colour calibration, stretch, deconvolution, saturation, the usual stuff. In photoshop some layer masked saturation/noise control/sharpness things. Didn't go too far on this one but i think with sharpening and maybe an HDR type process with layer masks there would be more in the image.

I cant advice on how to get results out of startools, because so far i have not had success with it. My tries with Startools always end up looking like they came out of Startools, and i dont think that's a great thing. I find real issue in how the colour module just doesn't seem to get real colour results out no matter what i do, and all the other modules slowly walk the image towards what you got out of it, a posterized and mushy looking image. Some might like the look of getting every bit out of an image but i think it detracts from the image. I see that some people get much better looking results than i can get out of it, so much of this is user error in my end, but i find other software much easier to use for processing.

One issue i found is that the image is 16-bit which is problematic for the faintest detail. I believe that is possibly a part of the issue with the posterized looking edges in Startools. Below is an image of the histogram in siril:

There are gaps in the histogram, meaning that the image has been stretched so far as to no longer fill all the values of a 16bit image. This can lead to abrubt looking edges in faint detail instead of evenly fading away into the background like it should be. Its not super obvious in this example and this is something many people dont bother with, but there is a difference in 32bit and 16bit processing and i think that's reason enough.

Why not try processing in SiriL though? Photometric colour calibration and a histogram transformation and you already have a real colour stretched image that you could then fiddle with in Photoshop or Gimp until the end of time until you get what you like.

Data is great by the way. Really nice capture.

That's really nice, much more pleasing on the eye.

'My tries with Startools always end up looking like they came out of Startools.'

I feel the same but I don't understand why the results look artificial. Maybe it's the colour and mushy look like you mentioned.

'One issue i found is that the image is 16-bit which is problematic for the faintest detail.'

I can restack from the start and save as 32 bit if you'd like to have another go? Maybe you could show the histogram of it like above, it would be interesting to see.

'Why not try processing in SiriL though?'

I'll try it. Startools seemed the most user friendly for beginners so I went with it. I've never used Gimp or Photoshop either, I wouldn't really know where to begin with them.

'Data is great by the way. Really nice capture.'

Thanks mate 👍

Edited April 5, 2022 by Pitch Black Skies

[Pitch Black Skies]

Has anyone got a link to a thread with a list of the different processing tools and a brief description of them?

Edited April 5, 2022 by Pitch Black Skies

[Jamgood]

1 hour ago, Pitch Black Skies said:

It's just that the guys here are able to produce a nice result with the DSS stacked file. It's more down to the post processing I think.

I know, isn't it infuriating!

APP does do some auto processing for you though, unlike DSS. 

I think it all just takes time to learn the art. I've only been at this hobby for a couple of years so I'm a master of nothing. Sadly, the processing learning curve is steep, regardless of the tools used and it is difficult to find the right tutorial for a one size fits all. Trial and error and applying new techniques as you go is the only way to learn really.

Have you tried using Starnet++ and processing target and stars separately? That is a good way of isolating different areas.

Edited April 5, 2022 by Jamgood

[alacant]

1 hour ago, Pitch Black Skies said:

results look artificial

You'd perhaps get more specific answers on the StarTools forum.

Cheers

[Pitch Black Skies]

37 minutes ago, Jamgood said:

I know, isn't it infuriating!

APP does do some auto processing for you though, unlike DSS. 

I think it all just takes time to learn the art. I've only been at this hobby for a couple of years so I'm a master of nothing. Sadly, the processing learning curve is steep, regardless of the tools used and it is difficult to find the right tutorial for a one size fits all. Trial and error and applying new techniques as you go is the only way to learn really.

Have you tried using Starnet++ and processing target and stars separately? That is a good way of isolating different areas.

Oh right, didn't know APP did that.

Maybe, however I'm beginning to think Startools is not the one for me. A few others here using Startools are getting the same artificial results.

I haven't tried that one yet, might be worth a try.

[Pitch Black Skies]

36 minutes ago, alacant said:

You'd perhaps get more specific answers on the StarTools forum.

Cheers

Good idea, didn't think of that.

[powerlord]

2 hours ago, Pitch Black Skies said:

Has anyone got a link to a thread with a list of the different processing tools and a brief description of them?

https://astrobackyard.com/resources/

[ONIKKINEN]

2 hours ago, Pitch Black Skies said:

That's really nice, much more pleasing on the eye.

'My tries with Startools always end up looking like they came out of Startools.'

I feel the same but I don't understand why the results look artificial. Maybe it's the colour and mushy look like you mentioned.

'One issue i found is that the image is 16-bit which is problematic for the faintest detail.'

I can restack from the start and save as 32 bit if you'd like to have another go? Maybe you could show the histogram of it like above, it would be interesting to see.

'Why not try processing in SiriL though?'

I'll try it. Startools seemed the most user friendly for beginners so I went with it. I've never used Gimp or Photoshop either, I wouldn't really know where to begin with them.

'Data is great by the way. Really nice capture.'

Thanks mate 👍

Startools is definitely the easiest software out there, i think. The module structure makes you work with at least a workable workflow and guarantees that there is an image in the end. Other dedicated astrophotography processing software might as well be voodoo for a beginner, none of it makes any sense at all when starting out.

Below is an image of what the histogra should look like after stretching, from one of my own projects:

Nice curve with no defined "end" to the data, it just slowly diffuses to the black and white ends.

The effect is probably small, or non existent if the person doing the processing is maybe not able to use all of the image but you have worked hard on a long integration, so taking the small steps is only a good thing. I think i may have stretched the image just a bit further to get the wispy stuff out more, and the core might be a bit better. There are no negatives to using a 32bit file for the linear part of the processing, other than a bit larger file size and maybe it draws more juice out of your PC. After stretching the added precision is not needed and you can save the image as 16-bit, if further processing software doesn't like 32-bit (like photoshop).

[alacant]

Hi everyone

I think it fair to say that you'll produce the best results using the app with which you're most familiar. Take the trouble to learn the idiosyncrasies of each and you'll be able to produce consistent results which are to YOUR satisfaction. 

Do we really want a thousand Andromeda galaxies all looking exactly the same? Sometimes it seems, we do!

We chose StarTools because it got us away from the endless mess of windows and collections of unrelated stretch-and-hope-for-the-best algorithms approach of other software. It is different. It works for US. If however the latter is what YOU find the best approach, then of course, stick with it; familiarity again. Those moving to StarTools from such apps are most likely going to find it more difficult to adapt. There are however migration guides. This one for example is aimed at Pixinsight users.

Stick to what you find best. If you're just beginning, try a few. It really doesn't matter which one you finally settle upon. They'll all get you there. 

Just our €0,02

Cheers

[powerlord]

Definately. Any tool can be used to overkill. Startools does have the unique quality that overkill renders a specific startoolsy effect which is unfortunate, but I've had results I love with it at times.

My advice is, first don't expect to just run up and start using a tool - they are all esoteric. watch a few youtube tutorials before you try. try free trials and decided what works for you and don't just go with what someone else says works or worse someone else says 'most people use XYZ' - wrong. afaik there's no proper surveys to show what most folk use.

when you decided what works for you, invest some time in learning it then, experimenting and yes..watching more tutorials.

Pity polls are not supported natively here, but suppose could add one... be interesting to know if there was some agreement, though most of us I think use more than one tool so it would only tell some of the story anyway.

my 2c: Much as PI would like to make you think processing astropics is rocket science it is actually no different from processing any other kind of photograph. Sure, there are some astro specific bits and bobs, but mostly its the same things - stretching, noise reduction, colour balance/saturation, masking and further tweaking. So it definately helps to have a tool like startools available to you (I purchased it), but mostly you'll do well if you understand the above stuff, how to work in layers, masking, blend modes, curves, levels, channels, what filters are useful (e.g. topaz), etc etc - all of that is bog standard photo editing 101. And applies to whatever you tool of choice is. PI just wraps a lot of it up in fancy names for ..reasons best know to the madness that created it... i.e. want to sharpen ? look for a sharpen filter in every single package out there.. oh expect PI, where you would use Deconvolution and MultiscaleLinearTransform. sigh.

So for what it's worth, I'd suggest trying startools, and following a few tutorials. I'd suggest also trying Affinity Photo and following some of James Ritson's tutorials. Try Siril, which is totally free, but again don't attempt it without wathcing a tutorial - Luke's are great on youtube (search for siril osc). And it's a no-brainer to get startnet2++ and learn to use it (gui on windows available, command line for mac) as it's free and one that is nearly universally agreed is a good thing to use.

My general workflow for galaxies is:

- stack in APP (but DSS would be fine)

- get rid of gradients, light pollution in APP (it's great at this, but Siril does it too easily)

- save it as unstetched fit.

- colour correct in Siril, with some saturation work, and stretch it and also save it as a 32bit floating tiff.

- load fit into startools and see if it 'works' for the image.

- if it does, bring result into affinity for tweaking

- if it doesn't load the tiff through starnet2++ and save.

- load both into affinity, create star mask layer.

- work on in and stars in affinity using all the regular tools, and topaz.

- save and publish.

[Bibabutzemann]

On 03/04/2022 at 18:42, Pitch Black Skies said:

@vlaiv  M101 19 hr 10 mn calibrated.zip 15.94 MB · 25 downloads

nice data, may i ask under which Bortle Sky this was taken? 🙂

[Pitch Black Skies]

6 hours ago, Bibabutzemann said:

nice data, may i ask under which Bortle Sky this was taken? 🙂

I think it's Bortle 4. What's a good website to find out?

All taken at new moon.

[Bibabutzemann]

44 minutes ago, Pitch Black Skies said:

I think it's Bortle 4. What's a good website to find out?

All taken at new moon.

https://www.lightpollutionmap.info/#zoom=1.19&lat=14.7492&lon=-96.9789&layers=B0FFFFFFFTFFFFFFFFFFF

This website will give you a rough estimate in your location. 

 

 

 

Edited April 5, 2022 by Bibabutzemann

[Pitch Black Skies]

Latest effort

[alacant]

On 06/04/2022 at 00:34, Pitch Black Skies said:

Latest effort

Hi

Much better.

Have a look at the ROI I posted here. Notice how it includes:

• the galaxy core
• an over exposed star
• background

I used HDR with shadows at 50%, context 17px and SVDecon in sampling mode. That will bring out the detail right to the core and ensure you lose none of the data. The stars are rather big so you may need to use Shrink. This will also avoid punching holes around the stars. 

HTH

Edited April 7, 2022 by alacant

[Pitch Black Skies]

1 hour ago, alacant said:

SVDecon in sampling mode

What should I be looking for in this mode?

Do you always use these modules too? Contrast, Sharpen, Entropy and Super Structure.

[Pitch Black Skies]

On 03/04/2022 at 20:44, alacant said:

If you want the Ha regions, stick the red in NBAccent.

Do I need to be shooting narrowband to do this?

[alacant]

2 hours ago, Pitch Black Skies said:

What should I be looking for

Unique to StarTools, and due to your data being held in a db, you can apply it anytime you like. Gone are the days of having to apply deconvolution to linear data. As indeed is the need to get your initial stretch just right.

https://www.startools.org/modules/sv-decon

Here's an example we took from our recent m81. Note in particular the detail emerging in the galaxy:

 

2 hours ago, Pitch Black Skies said:

Contrast, Sharpen, Entropy and Super Structure

Yes.

1 hour ago, Pitch Black Skies said:

narrowband to do this

No.

You could try Entropy with Ha or Compose. The latter works well if you have some frames taken with the red channel split from say, a UHC.

https://www.startools.org/modules/narrowband-accents/usage

--- --- ---

TBH, the best only way to get to grips with all this is to try it. Keep your data and go back to it as and when you have more experience.

For other POVs and use cases, don't forget the st forum.

Cheers and HTH.

Edited April 6, 2022 by alacant
ortografía

[Bibabutzemann]

On 06/04/2022 at 00:34, Pitch Black Skies said:

Latest effort

I have no idea how startools works but those big black halos around the stars make the image look unnatural. In PS/Darktable this happens when i sharpen too much or when the sharpen radius is too big.

Also i would really avoid clipping the background. You will loose so much of the precious data you collected. All the small galaxies in the background get lost. This also adds to an unnatural look. 

Third thing that stands out to me, that there are barely any colours left. But i guess this is preference.

Again, i dont know Star Tools and which steps causes these issues.

I only tried Star Tools in a trial period and realized i got faster the results i wanted with other software.

Just for fun i would try processing with Siril+ Darktable, which are both free and easy to use. 

 

 

[Pitch Black Skies]

5 hours ago, Bibabutzemann said:

I have no idea how startools works but those big black halos around the stars make the image look unnatural. In PS/Darktable this happens when i sharpen too much or when the sharpen radius is too big.

Also i would really avoid clipping the background. You will loose so much of the precious data you collected. All the small galaxies in the background get lost. This also adds to an unnatural look. 

Third thing that stands out to me, that there are barely any colours left. But i guess this is preference.

Again, i dont know Star Tools and which steps causes these issues.

I only tried Star Tools in a trial period and realized i got faster the results i wanted with other software.

Just for fun i would try processing with Siril+ Darktable, which are both free and easy to use. 

 

 

Thanks for the feedback, I'll have another attempt.

[tomato]

On 05/04/2022 at 23:34, Pitch Black Skies said:

Latest effort

I think the silvery tones are great but I agree the background is too dark and has clipped the faint regions. I find getting this right in Startools is one of the bigger challenges. In my experience, you need to spend some time carefully adjusting the parameters on the second AutoDev stretch, particularly the Ignore Fine Detail, shadow linearity and detector gamma functions, to get the optimum result. It’s very easy to clip the data.

[powerlord]

Some of that depends on personal preferences. For large galaxies where there are no others in the picture I'm happy to clip out all the background for example - replacing it with a 10/10/10 or so grey. For me, I like the look of a clean galaxy on a background of sharp stars. Even when I find startools works, usually what I find it gives me is a galaxy I like, but nothing else. So I take the galaxy out and pop it into a clean background, adding the stars from a startnet2++ starmask off a basic stretched image. That way you avoid all the 'startoolsy' weirdness it does with stars and backgrounds.

It's one the pleasures of the hobby isn't it ? You are in charge of what you create. 👍 That's why I'm an advocate of having a few tools in your toolbox - mix and match.