Crescent Nebula (NG...
 
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Crescent Nebula (NGC 6888)

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(@greg-erianne)
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This was an exercise in frustration last night (10/18)!  The forecast called for clear skies -- nope.  Clear...clouds...clear...clouds...etc., all night up until about 11:10 when I decided to call it looking out to the west and seeing a fresh batch of angry clouds and nearly solid overcast on the way! I think Lake Champlain kept sending presents my way.

Hope nobody else has as frustrating a time as I did.  

Anyway, I managed to salvage 1:42 min of subs (from what should have been about 3 hours).  That's something, anyway!

AT60ED w/ field flattener (360mm fL)
ASI2600MC Pro (OSC camera)
SkyGuider Pro with guiding via ASIAir Plus using an ASI120mm mini and a 30mm F4 guide scope
Antlia ALP-T Ha/OIII dual narrowband filter
180s x 34 [Total Exposure 1:42]; with dark, flat, and dark-flat frames 
Pre-processed in PixInsight and post-processed in Photoshop

Greg


   
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Terri Zittritsch
(@terri)
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Joined: 4 years ago
Posts: 310
 

Hi Greg, great image.  I love these wide fields.   I don't think I could get anywhere near that wide with anything I have except maybe a camera lens.   Great nebulosity  as well...    I was out there too, and not only were there more clouds than expected, but the seeing was horrible (at least at my house).    I was trying to validate the work done on my Celestron but the seeing was so bad and clouds so frequent I threw in the towel at around 11pm as well.   

Keep the great images coming!

Best,

Terri


   
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(@greg-erianne)
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Posted by: @terri

Hi Greg, great image.  I love these wide fields.   I don't think I could get anywhere near that wide with anything I have except maybe a camera lens.   Great nebulosity  as well...    I was out there too, and not only were there more clouds than expected, but the seeing was horrible (at least at my house).    I was trying to validate the work done on my Celestron but the seeing was so bad and clouds so frequent I threw in the towel at around 11pm as well.   

Keep the great images coming!

Best,

Terri

Sorry you had a frustrating night as well, Terri.  And on the flip side, I'd love to be able to do some close-up work!  [I thought I could use a Powermate for DSO imaging, but my results (and some 'kindly' phrased feedback on Cloudy Nights) put the kibosh on that idea quickly.  I'll just have to wait to get a bigger scope.]

The seeing wasn't very good at my house, either.  I had such high hopes for the night!  It was probably better I had to quit at 11 -- my granddaughter was nice enough to give me her nasty cold and it started working on me around 7:00 last night.  I was ready for bed, anyway!

Greg


   
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(@peter-gillette)
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Joined: 3 years ago
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Jeez, Greg!

That image is good enough to make me wonder just how much better it would be with hours of subs!

Very nice piece of work!

               -P-


   
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(@greg-erianne)
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Posted by: @peter-gillette

Jeez, Greg!

That image is good enough to make me wonder just how much better it would be with hours of subs!

Very nice piece of work!

               -P-

Thanks so much, Peter.  Those extra hours would add that nth degree of 'Wow!' (for me), I think.   The extra time on target would have allowed me to stretch the data just a bit more to pull out more detail without stretching noise and come away with a cleaner image.  Then again, I tend to obsess. 😀 

Greg


   
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(@peter-gillette)
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I look forward to comparing the results.

                                  -P-


   
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(@greg-erianne)
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Had to take a break from shoveling snow (ugh!) over the past few days, so I decided to learn/practice a couple of new things in PixInsight.  I reprocessed this Crescent Nebula data from last October (2022) entirely in PixInsight and took a stab at using a Foraxx palette (kind of a modified Hubble palette).  The data hasn't changed -- I used the 1:42 worth of data I had captured with my AT60 and my SkyGuider Pro (!) mount as described in the first post of this thread.

I went a little nuts on the nebula to try and bring out the OIII (using a lot of masking just for practice) so it really doesn't look natural. 

I can see the Soap Bubble Nebula (planetary nebula PN G75.5+1.7) a little more clearly with this palette.  It's the small circular area about 11 o'clock from the Crescent Nebula.  I think more integration time would bring this out better.  A small emission nebula, SH2-104, is in the upper left of the frame and is so bright that it can be seen with a large telescope.  

I'm very curious to see if this is improved when I use a slightly longer focal length on my 107PHQ to capture this again.  


   
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Terri Zittritsch
(@terri)
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Joined: 4 years ago
Posts: 310
 

Posted by: @greg-erianne

Had to take a break from shoveling snow (ugh!) over the past few days, so I decided to learn/practice a couple of new things in PixInsight.  I reprocessed this Crescent Nebula data from last October (2022) entirely in PixInsight and took a stab at using a Foraxx palette (kind of a modified Hubble palette).  The data hasn't changed -- I used the 1:42 worth of data I had captured with my AT60 and my SkyGuider Pro (!) mount as described in the first post of this thread.

I went a little nuts on the nebula to try and bring out the OIII (using a lot of masking just for practice) so it really doesn't look natural. 

I can see the Soap Bubble Nebula (planetary nebula PN G75.5+1.7) a little more clearly with this palette.  It's the small circular area about 11 o'clock from the Crescent Nebula.  I think more integration time would bring this out better.  A small emission nebula, SH2-104, is in the upper left of the frame and is so bright that it can be seen with a large telescope.  

I'm very curious to see if this is improved when I use a slightly longer focal length on my 107PHQ to capture this again.  

Nice soap bubble!!   Not sure I saw it before but it’s very clear here.  These wide fields show so much surrounding interest compared to my tight crops of objects (my typical shots).    I need to explore expanding my horizons… pun intended (smile).

 

Terri

 

 

 


   
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(@greg-erianne)
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@terri Honestly, Terri, I didn't even know it was there until I reprocessed the image and said, "What's that?"  🙄 

Greg


   
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