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Optolong L-extreme for me?

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#1 Eddie64

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Posted 03 March 2024 - 03:41 AM

Hi experts

i will be in a bortel 8-9 for a month soon and will have plenty of time and very likely plenty of clear highly polluted skies as well.

Am i right to think that this filter is what i need for my setup?

thanks and clear skies

Eddie



#2 daveco2

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Posted 03 March 2024 - 04:29 AM

Right.  You’ll be able to capture the Ha and Oiii bands.  They would be easy to separate, process separately, and recombine to RGB by different palettes.  Or just process together.  But you won’t be able to get Sii, for which you could use a separate filter.  Processing a Triband image gives many more palette possibilities.



#3 Eddie64

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Posted 03 March 2024 - 04:51 AM

Right.  You’ll be able to capture the Ha and Oiii bands.  They would be easy to separate, process separately, and recombine to RGB by different palettes.  Or just process together.  But you won’t be able to get Sii, for which you could use a separate filter.  Processing a Triband image gives many more palette possibilities.

so would i be better off with the L-enhance or a separate Sii filter? thanks


Edited by Eddie64, 03 March 2024 - 04:51 AM.


#4 jkelly

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Posted 03 March 2024 - 04:55 AM

if you have the filter on the entire session, you may need to increase the exposure time on polar alignment or focusing or plate solving a few seconds. Something like 3 or 5 second exposures with the filter on. There’s a general statement that these filters like longer subs…I’ve been fine with 60 second subs.



#5 acrh2

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Posted 03 March 2024 - 05:04 AM

There's gonna be no emission nebulae in a good position for imaging in a month in the Northern hemisphere. You might get 2 hours a night on something like Rosette and neighbors.

It's a galaxy season, totally unsuitable for imaging in an urban environment.


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#6 Eddie64

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Posted 03 March 2024 - 05:21 AM

There's gonna be no emission nebulae in a good position for imaging in a month in the Northern hemisphere. You might get 2 hours a night on something like Rosette and neighbors.

It's a galaxy season, totally unsuitable for imaging in an urban environment.

Very good point but according to stelerium I will have just about enough time and Alt on the rossette until end of March or so. thanks



#7 daveco2

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Posted 03 March 2024 - 06:57 AM

so would i be better off with the L-enhance or a separate Sii filter? thanks

The L Enhance expands the band around Oiii, so that won’t help.  The problem is that Sii is very close to Ha and the two cannot be separated if captured with the usual wider band filters.  You need a separate Sii filter.

 

I shoot galaxies from my Bortle 8/9 site.  The trick described by many here on CN is to take lots of short exposures, about 1 minute.  I use a mono camera and shoot 300xL, and 100 each of R, G, and B.   For you, with a OSC camera, try 200, 1 minute exposures.

 

The Cone Nebula is still available, 6pm to midnight. I’m waiting for a clear night.

Attached Thumbnails

  • RGB-PS-extremely small.jpg

Edited by daveco2, 03 March 2024 - 08:29 AM.

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#8 Eddie64

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Posted 03 March 2024 - 08:15 AM

The L Enhance expands the band around Oiii, so that won’t help.  The problem is that Sii is very close to Ha and the two cannot be separated if captured with the usual wider band filters.  You need a separate Sii filter.

 

I shoot galaxies from my Bortle 8/9 site.  The trick described by many here on CN is to take lots of short exposures, about 1 minute.  I use a mono camera and shoot 300xL, and 100 each of R, G, and B.   For you, with a OSC camera, try 200, 1 minute exposures.

 

The Cone Nebula is still available, 6pm to midnight. I’m waiting for a clear night.

ok thanks for that input.

Another question if i may: from what i read it seems to me that filters have to be of the same thickness? if so, which Sii filter would go alongside of the 1.85mm of the l-eXtreme?

many thanks



#9 daveco2

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Posted 03 March 2024 - 08:26 AM

ok thanks for that input.

Another question if i may: from what i read it seems to me that filters have to be of the same thickness? if so, which Sii filter would go alongside of the 1.85mm of the l-eXtreme?

many thanks

ZWO makes a 1.85 mm thick Sii filter.



#10 danny1976

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Posted 03 March 2024 - 01:28 PM

The L-eXtreme is a good filter. You can get a Askar D2 SII/OIII filter which allows you to do SHO images.



#11 WhitenerJ

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Posted 03 March 2024 - 05:33 PM

The L Enhance expands the band around Oiii, so that won’t help.  The problem is that Sii is very close to Ha and the two cannot be separated if captured with the usual wider band filters.  You need a separate Sii filter.

 

I shoot galaxies from my Bortle 8/9 site.  The trick described by many here on CN is to take lots of short exposures, about 1 minute.  I use a mono camera and shoot 300xL, and 100 each of R, G, and B.   For you, with a OSC camera, try 200, 1 minute exposures.

 

The Cone Nebula is still available, 6pm to midnight. I’m waiting for a clear night.

You shot this image of M51 from bortle 8-9? 



#12 daveco2

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Posted 03 March 2024 - 07:42 PM

You shot this image of M51 from bortle 8-9? 

Yes, from the sidewalk in front of my house in the Los Angeles basin.  Processing outlined by many here on CN.  I wasn't a believer at first, but the experts kept insisting it would work.

 

Attached - Spaghetti Nebula, shot through filters of course, very long integration time.  Askar FMA180, focal length 180 mm.

 

Of course, I would like to travel to a dark site to pick up more detail; but that trip hasn't happened over the last decade.  Now, I just take what I can get in high Bortle, whether galaxies or nebulae.

Attached Thumbnails

  • Forax_HOO-2-PS2-with reduced stars-very small.jpg

Edited by daveco2, 03 March 2024 - 07:45 PM.

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