Starless Trunk Mosaic

[Allinthehead]

Hi all, this is just a bit of fun experimenting with StarNet for Pixinsight. Thanks @Laurin Davefor helping with the install. This is 18 hours over three panels and 3 nights.

Esprit 100, Asi 1600 and Astrodon 5nm Ha filter.

What i was hoping is that someone would know how to add the stars back in. I have Photoshop and Pixinsight although my knowledge of the latter is quite limited.

Thanks for looking.

Richard.

[kirkster501]

Is this Starnet any good - I notice you still have a couple of them left in there?  I use Straton which is also superb and only costs about £10.  It struggles with very dense star fields though.

[alan potts]

Do you know it is funny, I found posts and video's on how to take the stars out but not one on how to put them back, mask them remove them, errrr, replace after masking, errrr No. BTW I rather like this without the stars leave it as it is

Alan 

[Allinthehead]

5 minutes ago, kirkster501 said:

Is this Starnet any good - I notice you still have a couple of them left in there?  I use Straton which is also superb and only costs about £10.  It struggles with very dense star fields though.

If you take another look you'll see that those aren't stars rather small bright Ha regions. 

StarNet is a free Pixinsight module and since this is my first time trying this I'm afraid i don't have any reference to say whether or not it's any good but it did a decent job here. 

[jjosefsen]

I found that Starnet makes some pretty good starmasks, something i've always struggled with in PI. :)

[Allinthehead]

5 minutes ago, alan potts said:

Do you know it is funny, I found posts and video's on how to take the stars out but not one on how to put them back, mask them remove them, errrr, replace after masking, errrr No. BTW I rather like this without the stars leave it as it is

Alan 

Thanks Alan. Ya I've struggled trying to get them back in. I assume some sort of star mask and adding them back in by just selecting the stars but I'm not managing so far.

[Allinthehead]

2 minutes ago, jjosefsen said:

I found that Starnet makes some pretty good starmasks, something i've always struggled with in PI.

Thanks. Must give this a try. I failed using PS 

[Xiga]

3 hours ago, Allinthehead said:

Hi all, this is just a bit of fun experimenting with StarNet for Pixinsight. Thanks @Laurin Davefor helping with the install. This is 18 hours over three panels and 3 nights.

Esprit 100, Asi 1600 and Astrodon 5nm Ha filter.

What i was hoping is that someone would know how to add the stars back in. I have Photoshop and Pixinsight although my knowledge of the latter is quite limited.

Thanks for looking.

Richard.

Adding the Ha stars back in is actually pretty simple. In PS, just layer the starless image on top of the regular Ha image (the version you ran Starnet on) and change the blend mode to either Difference or Subtraction. This should leave you with just the stars showing. Flatten and save, and then layer this 'Stars only' image back on top of the starless (Starnet) one, with a blend mode of Lighten. Only the Ha stars should now be getting added. This method works great for NB, as you can keep the stars and nebulosity separated, which makes processing much easier.

Oh, nice image btw Richard! 👍 That's some size FOV!

Edited October 16, 2019 by Xiga

[Laurin Dave]

Very nice Richard, lovely field of view..  I’m finding StarNet to be a very useful tool..  

Dave

[Allinthehead]

10 hours ago, Xiga said:

Adding the Ha stars back in is actually pretty simple. In PS, just layer the starless image on top of the regular Ha image (the version you ran Starnet on) and change the blend mode to either Difference or Subtraction. This should leave you with just the stars showing. Flatten and save, and then layer this 'Stars only' image back on top of the starless (Starnet) one, with a blend mode of Lighten. Only the Ha stars should now be getting added. This method works great for NB, as you can keep the stars and nebulosity separated, which makes processing much easier.

Oh, nice image btw Richard! 👍 That's some size FOV!

Thanks Ciarán. I'll give that a try this evening.

 

8 hours ago, Laurin Dave said:

Very nice Richard, lovely field of view..  I’m finding StarNet to be a very useful tool..  

Dave

Thanks Dave. It did very well removing some large stars including the Garnet with a quick go after using the healing brush.

[lux eterna]

14 hours ago, Allinthehead said:

... how to add the stars back in. I have Photoshop and Pixinsight although my knowledge of the latter is quite limited.

My way of doing that is this: Stack and process a new image with priority for the stars (moderate stretching, good colours and sizes etc). With the starless layer as the bottom layer, put the new one on top and change the star layer´s blending mode to lighten. Then, to make it blend in nicely, create a curves or levels layer (above the star layer) with a clipping mask (so it only affects the star layer). Then tune the adjustment layer until the stars look natural.

Ragnar

[Allinthehead]

Thanks Ragnar I'll have a go at this when i get a chance. 

[kirkster501]

I also installed Starnet.  It is superb.

[Rattler]

Great image. I tried adding Starnet in Pixinsight the other day and for some reason it doesn't find it. I added the file to the bin folder and followed the instructions but it's not detected. Any ideas?

[Laurin Dave]

It won’t work on Macs from before 2012 or thereabouts..  so if that’s what you’ve got that’s the reason..   

[emyliano2000]

On 16/10/2019 at 18:29, Allinthehead said:

Hi all, this is just a bit of fun experimenting with StarNet for Pixinsight. Thanks @Laurin Davefor helping with the install. This is 18 hours over three panels and 3 nights.

Esprit 100, Asi 1600 and Astrodon 5nm Ha filter.

What i was hoping is that someone would know how to add the stars back in. I have Photoshop and Pixinsight although my knowledge of the latter is quite limited.

Thanks for looking.

Richard.

Wow, this looks so good. 

I tried soooo many times the star removal but I never got a good result. 

I have no clue how you guys are doing it. 😢

I have the pixinsight starnet plugin, I have the standalone version too, Annie's action pack in Ps, Straton. Tried them all and I just can't get a good result. 

Would you mind sharing how you are doing it please, do you do it on a stretched or unstretched photo? At what point in the process do you do it? 

And lately I get an error when trying the pix plugin, Check point not found or something like that. 

Emil

[Yawning Angel]

5 hours ago, Rattler said:

I added the file to the bin folder and followed the instructions but it's not detected. Any ideas?

Add just the files to the Bin folder, don't create a starnet subfolder

[Rattler]

22 minutes ago, Yawning Angel said:

Add just the files to the Bin folder, don't create a starnet subfolder

Ah I see. That may be the issue. Cheers.

[steppenwolf]

On 16/10/2019 at 18:29, Allinthehead said:

What i was hoping is that someone would know how to add the stars back in. I have Photoshop and Pixinsight although my knowledge of the latter is quite limited.

It is relatively easy to recombine the stars using PixInsight. Open both the starless and stars only versions of your processed data then open the PixelMath Process. Select ‘Use a single RGB/K expression’ and ‘Generate output’. Enable ‘Create new image’ and enter a name for the finished image in the ‘Image Id’ box, leaving all the other settings at their defaults. Click on ‘Expression Editor’ and type in the following two calculations:-

iif((Stars_only_image_name <=0.01), Stars_only_image_name, 0.001);
~(~Starless_image_name * ~Stars_only_image_name)

Replace the two image names above with those of your own images. You can select these from the list of open files in the top pane of the Expression Editor page. Click on ‘OK’ then click on the Apply.

 

[Allinthehead]

On 18/10/2019 at 08:24, Rattler said:

Great image. I tried adding Starnet in Pixinsight the other day and for some reason it doesn't find it. I added the file to the bin folder and followed the instructions but it's not detected. Any ideas?

Thanks. As already mentioned by Alex add the files individually. I made the same mistake.

 

On 18/10/2019 at 11:39, emyliano2000 said:

Wow, this looks so good. 

I tried soooo many times the star removal but I never got a good result. 

I have no clue how you guys are doing it. 😢

I have the pixinsight starnet plugin, I have the standalone version too, Annie's action pack in Ps, Straton. Tried them all and I just can't get a good result. 

Would you mind sharing how you are doing it please, do you do it on a stretched or unstretched photo? At what point in the process do you do it? 

And lately I get an error when trying the pix plugin, Check point not found or something like that. 

Thanks. I just used the default setting in StarNet on an image stretched to approx 80% of final result. I then brought the starless image into PS and used the healing brush around the areas affected by the star removal.

17 hours ago, steppenwolf said:

It is relatively easy to recombine the stars using PixInsight. Open both the starless and stars only versions of your processed data then open the PixelMath Process. Select ‘Use a single RGB/K expression’ and ‘Generate output’. Enable ‘Create new image’ and enter a name for the finished image in the ‘Image Id’ box, leaving all the other settings at their defaults. Click on ‘Expression Editor’ and type in the following two calculations:-

iif((Stars_only_image_name <=0.01), Stars_only_image_name, 0.001);
~(~Starless_image_name * ~Stars_only_image_name)

Replace the two image names above with those of your own images. You can select these from the list of open files in the top pane of the Expression Editor page. Click on ‘OK’ then click on the Apply.

 

Thanks for that Steve. I will try in both PS and PI now. 

[Rodd]

Very dramatic.  I was going to comment of putting stars back i PI--but Richard said it better than I ever could

Rodd

[david_taurus83]

On 18/10/2019 at 11:39, emyliano2000 said:

Wow, this looks so good. 

I tried soooo many times the star removal but I never got a good result. 

I have no clue how you guys are doing it. 😢

I have the pixinsight starnet plugin, I have the standalone version too, Annie's action pack in Ps, Straton. Tried them all and I just can't get a good result. 

Would you mind sharing how you are doing it please, do you do it on a stretched or unstretched photo? At what point in the process do you do it? 

And lately I get an error when trying the pix plugin, Check point not found or something like that. 

Emil

Hi Emil. It will only work on a non linear image. So after your main stretch. It wont work on a project you have already started. What I mean is, save the stretched image you want to work on.  Save your project and close Pixinsight. Restart Pixinsight and load the Starnet process first. Now load up the saved image and drag the Starnet instance onto the image. It works well on Ha images as the stars tend to be small. On other images with big stars, bloated stars, halos etc, it will leave artifacts behind.

[emyliano2000]

6 hours ago, david_taurus83 said:

Hi Emil. It will only work on a non linear image. So after your main stretch. It wont work on a project you have already started. What I mean is, save the stretched image you want to work on.  Save your project and close Pixinsight. Restart Pixinsight and load the Starnet process first. Now load up the saved image and drag the Starnet instance onto the image. It works well on Ha images as the stars tend to be small. On other images with big stars, bloated stars, halos etc, it will leave artifacts behind.

Thank you so much. I have a feeling that it will work. I ve done it quickly on a partially stretched RGB photo and I like what I see. Can't wait to try it on the individual Ha, Sii and Oiii

Emil

[emyliano2000]

I tried on the partially stretched Ha stack and this is my result.

My stars are very fat even in the Ha stack and I had, still have quite a few residues.

How do you clean them. I ran the Spot Healing brush tool on most of them. Is there any other way to make them blend with the surrounding area?

I'm not really a fan of starless but I really want small stars in my SHO photos and if this will help me do it , so be it.

Emil

[apolkowski]

On 18/10/2019 at 21:56, steppenwolf said:

It is relatively easy to recombine the stars using PixInsight. Open both the starless and stars only versions of your processed data then open the PixelMath Process. Select ‘Use a single RGB/K expression’ and ‘Generate output’. Enable ‘Create new image’ and enter a name for the finished image in the ‘Image Id’ box, leaving all the other settings at their defaults. Click on ‘Expression Editor’ and type in the following two calculations:-

iif((Stars_only_image_name <=0.01), Stars_only_image_name, 0.001);
~(~Starless_image_name * ~Stars_only_image_name)

Replace the two image names above with those of your own images. You can select these from the list of open files in the top pane of the Expression Editor page. Click on ‘OK’ then click on the Apply.

 

I am sorry for reanimating this old thread, but I have a couple of questions. First, to my logic, the first expression sets value of 0.001 to all pixels with value higher than 0.01. Should it be opposite? If I run this expression alone in PixelMath, I kill all stars in the star mask.

Second, the end result is OK, images are nicely combined, but changing parameters in the first expression has no influence on the final image. It means to me, that the change to star mask in expression 1 has no impact on the final result, as PixelMath uses the original starless image for combinantion. So destroying the star mask by the error in expression 1 is not visible in the end result.

Please correct me if I am wrong and my logic makes no sense.