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M16 - Eagle Nebula


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5 minutes ago, paulgrover68 said:

Last night was only meant to be about equipment testing - I've reconfigured the 130's rig a little and 72EDF a lot.  72EDF still needs a few bits.

This was on the 130. I used every minute of the 2 hours of fake darkness to grab this... 32 x 240 second exposures.  If next weekend is clear I'll add some more data.

I must sort a rotator for the big scope, as it;s not framed as I would ideally like. May have over processed a bit... out of practice
 

M16 - The Eagle Nebula

 

 

Looks great for just a couple of hours. I wouldn't say it's over processed, the details are nice and sharp. Maybe the stars are a little saturated, but that is an easy fix.
 

Brian

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4 hours ago, AstronomyUkraine said:

 

Looks great for just a couple of hours. I wouldn't say it's over processed, the details are nice and sharp. Maybe the stars are a little saturated, but that is an easy fix.
 

Brian

I've been leaning a bit heavily on the StarShrink plug. While stuck in a traffic jam I realised I'm pushing the curves up and then expecting the plug in to pull them back - which is a bit silly.

 

So I just went back and had a go at creating a star mask in photoshop - result was a pretty good. I use a far less aggresive star shrink and stuff it works quite well.

Saturated and bloated stars are my current nemesis - any suggestions very welcome as my success in dealing with them has been hit and miss.

I've also been without data for so long I need to slow down my processing - I'm rushing through actions just to get an image and inevitably I find myself going back and starting over!

 

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27 minutes ago, paulgrover68 said:

I've been leaning a bit heavily on the StarShrink plug. While stuck in a traffic jam I realised I'm pushing the curves up and then expecting the plug in to pull them back - which is a bit silly.

 

So I just went back and had a go at creating a star mask in photoshop - result was a pretty good. I use a far less aggresive star shrink and stuff it works quite well.

Saturated and bloated stars are my current nemesis - any suggestions very welcome as my success in dealing with them has been hit and miss.

I've also been without data for so long I need to slow down my processing - I'm rushing through actions just to get an image and inevitably I find myself going back and starting over!

 

The best tool to avoid oversaturating your stars is Starnet++. Use it on your stack just before it's fully stretched, then reintroduce the stars after stretching and colour correction. I don't use Photoshop for processing astro images. Photoshop users on here probably have other methods to avoid bloated stars, this is the process I use in Pixinsight.

Edited by AstronomyUkraine
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46 minutes ago, David said:

Nice image Paul. As you found out, star masks in PS help. 
 

Just googled images of Sinclair’s ZX81 after seeing your kit list. That was a blast from the past. 

The dreaded RAM pack wobble - usually after you'd spent a whole day of the summer holidays typing in the game code from a listing in Computer & Video Games magazine

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46 minutes ago, paulgrover68 said:

The dreaded RAM pack wobble - usually after you'd spent a whole day of the summer holidays typing in the game code from a listing in Computer & Video Games magazine

I vero-wrapped my own home brew 64kb RAM pack and soldered it in to the expansion connector  - no wobble!

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I decided to pursue the Starnet ++ route.  I had some issues on my Mac, so had my PC do the work.  This actually worked well as I could do other stuff while the stars were removed.

This result is far from perfect - I have some halos and more artefacts than the V & A.  I can see is how powerful this is and I'm encouraged to experiment more.  I included the starless image here just for reference (it shows some of the oddities).  I think much of this is due to working with an image I'd already applied a lot of processing to (notably starshrink) I will do a from scratch process on this or my next set of data.
 

M16 with fixed stars

 

and the interim starless version

 

m16-starless

 

I probably would not have experimented with this had it not been for this thread - so many thanks. I still have much to learn, but it's not a chore to learn it.

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56 minutes ago, paulgrover68 said:

I probably would not have experimented with this had it not been for this thread - so many thanks. I still have much to learn, but it's not a chore to learn it.

The trick to get the most out of Starnet++ is to remove the leftover halos and artifacts, before reintegrating the stars. The best method is by using the clone stamp tool set to a low opacity, around 10% works well. Set the radius to the approximate size of the artifact, and sample close to the artifact to remove it. It a laborious job, but the results are well worth it.

 

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19 minutes ago, paulgrover68 said:

Excellent - I figured that might be a possibility. I was initially fooling with layer mask on the dark areas to mask them out.  That'll be my homework for tomorrow!

Forgot to say. I only mentioned the clone stamp tool for removing artifacts, because that the only tool available in Pixinsight for removing artifacts. In Photoshop you have a variety of different tools that might work better than the clone stamp.

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I do this in Gimp and I like the Heal tool. After stacking and a very light stretch, apply starnet++ to extract the starless image. Subtract this in Gimp/PS from the original to isolate the star field. Stretch and process the starless as you see fit, including cloning/stamping/healing the artefacts out, and merge the stars back on top with 'lighten only' blend mode.

 

I sometimes also apply the stars a second time in 'normal' mode. If the stars are slightly saturated, this can 'fill in' the cores, reduce the halos, and make them look a little more natural overall. It's useful if you have a natural colour halo, with a white saturated core.

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Beautiful.  I prefer your first version with the stars though.  Really sharp and crisp.  Was that with the ASI294MC Pro?  I have just bought the mono version.

Edited by Gina
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2 hours ago, Gina said:

Beautiful.  I prefer your first version with the stars though.  Really sharp and crisp.  Was that with the ASI294MC Pro?  I have just bought the mono version.

Yes this was the 294MC-Pro. I've had it about a year now and no complaints.  When I go mono I'll probably go with the mono version as the sensor matches well with my scopes.


 

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1 hour ago, MarkAR said:

Very good result for a test run.

I was genuinely surprised by how good it came "out of the box"  I've since reprocessed some old data and results have been a little mixed. There are definitly more I need to learn on this.  What's encouraging I'm seeing a path from where I am to where I want to be next... just haven't quite worked out the route yet...

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1 hour ago, paulgrover68 said:

I was genuinely surprised by how good it came "out of the box"  I've since reprocessed some old data and results have been a little mixed. There are definitly more I need to learn on this.  What's encouraging I'm seeing a path from where I am to where I want to be next... just haven't quite worked out the route yet...

Practice practice practice.

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