Sharp Edge to halos left after Fringe killer

[AstroNebulee]

Hi
I am using star tools 1.8 and after using fringe killer in the filter module im left with a grey halo that i just cannot get rid of in any other module.

Could someone please help me in bringing the halo tighter to the star core.
My workflow to this point is:
Autodev-Bin-Crop-Wipe-Autodev (with roi)-Contrast-HDR-Sharp-SV decon sv mode-Colour-Filter fringe killer.
I have tried lots of combinations in the shrink module but cannot get rid of it.
My setup is skywatcher 72ed az gti in eq mode, zwo 294 mcpro with 2 inch zwo ir uv cut filter, guiding with zwo f4 guidescope using an asiair pro.

Kind Regards

Lee

[happy-kat]

Several ideas on this thread
viewtopic.php?f=6&t=924

[AstroNebulee]

Thank you, I have been having a play all weekend so far and think I'm getfing somewhere slowly. Trying to work out a good workflow on this involving star tools and photoshop tweaks. Will post up my findings when finalised

[AstroNebulee]

Reading through this section of the forum I know see that my stars don't have halos and are how the stars are truly meant to look with a tight centre and the glow around it.
Just trying to soften the edges around the stars is really the issue now. I think after a day or two over the weekend and hopefully tonight as its due to be cloudy I can test out the processing more.
Reading through the other posts maybe my setup being undersampling is not helping issues. It seems my set up works better with poor seeing using this calculator on astronomy tools website.
Cheers
Lee

[Mike in Rancho]

I believe Fringe Killer is more of a color thing, slowly fading or desaturating the color line clicked on. It'll help make things like bright blue/purple "halos" less noticeable, but of course it's in the data, so still there.

You might try different things in AutoDev, if you want, that may provide less of the prominent diffraction areas around stars. Mostly those are your Ignore Fine Detail and ROI settings. It's a balance against the other detail you want to show in the nebulosity. But also, if for example you push the IFD up pretty high (past the point of the background darkening) some stuff can begin getting brighter, including the outer reaches of stars.

I don't know if you are being harmed by undersampling, much goes into that including of course your seeing. Does that camera have the unlocked bin mode (I forget if that is bin1 or bin2) for smaller pixels? That would take you down to around 2.3 instead of 4.6, but your files will be very large, like over 8000 pixels wide. I know some with the 294MM that do that quite frequently, though with a WO81GT and reducer, so their focal length is actually down in the 300's.

[AstroNebulee]

Hi
Thank you for your reply. I'm not sure if my camera has the unlocked binning mode, I'm pretty much a noon and only had it for a few months.
have been trying all weekend to get some sort of workflow sorted for this issue. I have also been reading a lot in the star tools forum and realise the stars aren't meant to be this way rather than blobs.

Theses are very roughly processed and not had the final tweak in photoshop but I'm much happier with these.

I'll post a screenshot of my scribbling workflow if anyone can decipher it. There are two examples one uding an extra shrink module with halo extend and one with using the flux module and noise. It still needs a tweak here and there but I'm much happier now
It was easy removing the purple /blue fringing.

I used the repair module to reshape the stars as I have an eggy issue (maybe I can fo away with the repair as SV decon does a pretty good job and I've hopefully sorted the back spacing in the camera better) But if I didn't use the repair module the edges of the stars looked better.

To remove the grey halo around the star core I wert back into filter created the mask for stars and then chose 'nudge screen' and clicked the grey halo part which lightened it.

Then I'm trying to soften the edges of the halo, the inage using the extra shrink worked best, still a lot of playing about to do but progress made I think.

If you can decipher my scratch pad good luck haha, the other side is worse. It will need a touch of tweaking but the body of it is there now.
I know some modules are out of order here but it is open to tweaking now if finally got an image I like. I feel the image using the entropy is giving me softer edges to the stars but still kerping the core visable.
Reading the notes in the manual, the synth module may be my friend here in helping with the edges of the stars.

[AstroNebulee]

Had another quick tweak tonight, basically moved the entropy module up, used the synth module and then used the second shrink module as a final step. Not sure where the purple hue has come from (looked good on the laptop) but yet to tweak in photoshop, but ok I think. Also reduced the green bias slider in colour module.

[Mike in Rancho]

Hmmmm....

Well, for one I like your notes! I remember first starting ST and charting out all the module names on a yellow pad too.

Now I just consult the log, especially for looking at prior processing. Whenever I close ST I go into the distro folder and rename the log file so it can be identified. ST will either make a new one when you start the program again, or it will keep adding on to the prior log (which can start getting big).

You're throwing a lot of stuff at these stars, but I'm not sure it'll all help. The nudge in filter was to now brighten the halos/diffraction and make them seem like bigger stars?

If you want to share your stack we can help see what might be there or could be done. Depends on your goal of what the stars should look like, of course, and if getting there is reasonably doable.

And I think you answered yourself on the purple. Reducing relative green is kind of tantamount to an increase of red and blue. And red+blue = ???

But on top of that, there's a good possibility you may also need to calibrate your computer monitors. Until I got one of those x-rite thingies, my laptop and desktop disagreed on color by a lot.

[AstroNebulee]

Hi Mike
I will try to share my stack on Dropbox here, hopefully it works, it's quite rubbish but using it as a test image from old data taken in February.

https://www.dropbox.com/s/8ju3zgg7d4pkv ... e.fit?dl=0

I prefer to make the notes and I have it all there on hand at the time and can alter it.
I think if I take out the screen nudge in the filter module and just use the synth at the end may help.
Maybe my monitor needs calibrating properly but I have done this and the images still don't match against devices and laptop, probably something I'm doing when saving in photoshop.
I will lessen the amount of use on the green bias slider next time.
What I'm looking for in the stars are not blobs of light but the star tools stars (if you know what I mean with the sharp centre point of light) but I'd like the edges of the 'halo' left behind after using the fringe killer to be lighter and more soft edged. Reading in the special techniques part of the manual could this be what I'm looking for? Improve the stellar profile of the star in layer module.
Cheers

Lee

[AstroNebulee]

Had another retweak tonight quickly before setting my scope up. I'll include the log file. I did away with the screen nudge and synth modules and did a stellar profile tweakin layers. The stars are how I want them with a smooth edge and clear points of light at the centre, just think I've gone overkill on the noise reduction. Still need to home in some parts but it's definitely an improvement on my very first post I think.
https://www.dropbox.com/s/ufkwcvvc2j73f ... .tiff?dl=0

https://www.dropbox.com/s/95qtu5zuid8tg ... s.log?dl=0

Cheers

Lee