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  #21  
Old 04-05-2022, 03:19 PM
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pmrid (Peter)
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Looking at the Antlia images Doug posted below, and comparing with my L- Enhance images, I am struck by the lack of “bloom” around the stars with the Antlia. I have been imaging with 2 different 72mm achromats so I expect some fringe effects but am surprised by the extent of it. I had expected that with the dual band filters, much of this would be avoided. It doesn’t look that way though.

Any tips on Photoshop processing it out?
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Last edited by pmrid; 04-05-2022 at 04:17 PM.
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  #22  
Old 07-05-2022, 10:35 AM
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Retrograde (Pete)
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Interesting - it looks like everything is just a little out of focus.

Given that each band is in a different part of the spectrum an achromat is likely to have some trouble I guess?
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  #23  
Old 07-05-2022, 12:33 PM
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pmrid (Peter)
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Hi Pete.
yes, it looks that way but both images (2 different scopes) was focused by ASiair’s autofocus routine. Since each image was taken through a L-Enhance filter, where the bands are red(Ha) and Blue/green), and since the scopes are achromats, some CA is to be expected I suppose. So ASiair autofocus routine must prioritise one band over the other. Not much I can do about that I suppose.
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  #24  
Old 13-05-2022, 12:26 PM
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Astro_Girl (Cheryl)
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Hi there,

Would you happen to have or are able to obtain a test shot of a bright star say Acrux 30 seconds plus exposure using the Antlia filter and post it here.

I am in the market for one but am interested to see what if any haloing is present.

Cheers,
Cheryl
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  #25  
Old 14-05-2022, 09:35 AM
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Hi Peter,

I have used a little manual lense correction in PS Light Room developing to get rid of the coloured fringing. It works if used gently on one particular colour and you can choose which colour to work on . Blue fringing is particularly easy.

I am sure the same lense correction would be available in PS also. LR is easy for me.



Quote:
Originally Posted by pmrid View Post
Looking at the Antlia images Doug posted below, and comparing with my L- Enhance images, I am struck by the lack of “bloom” around the stars with the Antlia. I have been imaging with 2 different 72mm achromats so I expect some fringe effects but am surprised by the extent of it. I had expected that with the dual band filters, much of this would be avoided. It doesn’t look that way though.

Any tips on Photoshop processing it out?
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  #26  
Old 14-05-2022, 12:50 PM
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Quote:
Originally Posted by Astro_Girl View Post
Hi there,

Would you happen to have or are able to obtain a test shot of a bright star say Acrux 30 seconds plus exposure using the Antlia filter and post it here.

I am in the market for one but am interested to see what if any haloing is present.

Cheers,
Cheryl
It's not Acrux but here's a 100% crop of Lambda Centauri (which is still quite bright) with the Antila through my little ED65.
All that has been done is a basic stretch and crop (also added the full frame with basic stretch to give some context)

Hope this gives some insight,
Pete
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  #27  
Old 16-06-2022, 11:52 AM
evltoy (Wayne)
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I’m so glad I found this thread as I’m currently trying to work out which way to go. If any of you guys can give me some direction that would be awesome.

I’m looking at getting both the L-eNhance and L-eXtreme (1.25”) to add to my filter collection which includes a ZWO Duo and a Baader Moon/Sky Glow. My gear is the asi294MC pro, SW ed80 & ed120 and a Celestron 8” SCT. My F-stop is no more than F6 and I don’t plan to go past f4 in the future. I live mainly in bortle 5/6 and my holiday area is 3.

Given that these filters are no good for Galaxies or Reflection Nebula's I would be instead using the SCT with the baader Moon/Sky glow or just the UV/IR filter with the 294MC.

My delimer is, is the L-eXtreme going to be worth it considering the narrow band pass of HA or do I get the L-eNhance 1.25” for the asi294 and another L-eNhance 2” for my unmodified DSLR to run on either the ed80 or ed120? Getting the L-eNhance 2” would allow me run 2 setups at a time.

What are your thoughts?

FYI – Cuiv just released a new vid 4 days ago with some interesting info on the filters we are talking about.
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  #28  
Old 24-06-2022, 10:34 AM
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A point to bear in mind is that both refractors you mention are achromats which means they are not as colour-corrected as a triplet or better. That means your dual-band filters are likely to show some bloom around stars. That’s because the red and blue components are not coming to best focus at the same place.

The Ha bandpass in filters like the Enhance is comparatively wide (about 20nm or so from memory; and the blue/green bandpass is even wider I think.) If you compare results with a mono ccd and discrete NB filters, the difference will be quite marked.
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  #29  
Old 24-06-2022, 12:52 PM
evltoy (Wayne)
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Hi Peter

Thank you for the information you have provided, but I'm not sure if I have missed your point... I dont have a mono camera in my setup to compare.


I'm more asking would I be better off with 2x L-eNhance filters running on my ED80 & ED120 with the 294MC and DSLR (non-modified) at the same time

or

would the L-eNhance & L-eXtreme combo serve me better just on the 294MC only.

Another way to look at it... Will I get more benefit from having the L-eXtreme in my kit over being able to run 2 rigs at the same time with both on the L-eNhance

Cheers
Wayne
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  #30  
Old 24-06-2022, 08:25 PM
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pmrid (Peter)
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Quote:
Originally Posted by evltoy View Post
Hi Peter

Thank you for the information you have provided, but I'm not sure if I have missed your point... I dont have a mono camera in my setup to compare.


I'm more asking would I be better off with 2x L-eNhance filters running on my ED80 & ED120 with the 294MC and DSLR (non-modified) at the same time

or

would the L-eNhance & L-eXtreme combo serve me better just on the 294MC only.

Another way to look at it... Will I get more benefit from having the L-eXtreme in my kit over being able to run 2 rigs at the same time with both on the L-eNhance

Cheers
Wayne
I guess the suggestion I was making was that with the amount of $$ you’re looking to spend, you may want to consider the alternatives first - mono ccd and NB filters.


Peter
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  #31  
Old 24-06-2022, 08:31 PM
evltoy (Wayne)
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Ahh ok. Nope mono camera/setup is out the question… don’t have the time or enough clear skies.

Also You couldn’t get a mono camera and NB filter secondhand for the cost of the 2 filters ($700).
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