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Filter recommendations to avoid these huge halos?

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5 replies to this topic

#1 dgpilot

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Posted 08 August 2020 - 12:51 AM

Hi all, 

 

I currently have ZWO SHO 1.25" filters mounted in the ZWO 8 position EFW. These filters make processing a nightmare. Take a look at one 300s OIII shot: 

 

Screen Shot 2020-08-07 at 10.43.21 PM.jpg

 

 

I'd love to hear any recommendations for filters that do not do this, and can mount into my ZWO EFW.. I realize they are more expensive. On the other hand I am happy with the LRGB ones I have mounted in the same EFW.

Also, do good quality filters reduce star size?



#2 pyrasanth

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Posted 08 August 2020 - 12:58 AM

I would look at Chroma or Astrodon with a leaning toward Chroma in the light of recent changes that have happened with Astrodon. These filters are guaranteed halo free.

 

I've had some success with cheaper Baader filters and have never seen halo's as bad with the OIII as to what you have presented. 

 

You would need to check carefully that the selected option will fit your filter wheel- I can't advise on that.


Edited by pyrasanth, 08 August 2020 - 12:59 AM.

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#3 dron2015

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Posted 08 August 2020 - 01:09 AM

I would look at Chroma or Astrodon with a leaning toward Chroma in the light of recent changes that have happened with Astrodon. These filters are guaranteed halo free.

 

I've had some success with cheaper Baader filters and have never seen halo's as bad with the OIII as to what you have presented. 

 

You would need to check carefully that the selected option will fit your filter wheel- I can't advise on that.

And what exactly happened w/ Astrodon? I ordered SII NB - it took a bit some time but it was delivered to me.



#4 sg6

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Posted 08 August 2020 - 01:18 AM

One thing is to keep the problem hightlighted, here and elsewhere if possible. Then maybe ZWO would sell filters that have ZWO on them, go in to ZWO equipment and do not produce what are appauling halos on images.

 

Isn't it rather poor that a company most certainly dedicated to astroimaging produces equipment that performs as poorly as this?

 

Have said a few times that astronomers accept second or third rate equipment but just accept it. Looking at it you have managed to waste $130 or thereabouts.



#5 dgpilot

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Posted 08 August 2020 - 08:47 AM

Would this filter work in the ZWO EFW?

https://optcorp.com/...lpha-5nm-filter

 

How does it mount? There's not much info on it


Edited by dgpilot, 08 August 2020 - 09:27 AM.


#6 pyrasanth

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Posted 11 August 2020 - 04:57 AM

And what exactly happened w/ Astrodon? I ordered SII NB - it took a bit some time but it was delivered to me.

The business changed ownership & during that transition there were a few undesirable issues reported on this & other forums.




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