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A patchwork of nebulae


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Tremendous conditions followed a deep blue late afternoon sky of rare intensity. These are the best views I've had so far of many faint nebulae, but I was also surprised to struggle and even fail on a couple of new ones given the quality of the conditions. Were these targets (the Cave Nebula and to a lesser extent the Bubble and Cocoon) simply much tougher than the rest, or is the advantage of having seen a faint feature previously really so great? At least one observation (a nebula extending from the Crescent) where I believe I got it wrong too, although I was certainly rushing in my excitement at the conditions.

Also, in one beautiful amble through the summer Milky Way, I came to see this area as a connected whole for the first time rather than a set of isolated numbered objects. A nebula flowing into a cluster into a dark starless void into a rich sparkling field with yet more nebulosity. It was wonderful.

Nice to share the experience with two chaps who were out imaging the same faint targets too. I felt like a caveman with my low tech mirror mounted on chipboard...

10" dob and 10x50 handheld binos used throughout. NELM a bit better than 6 although I didn't actually check.

Barnard's Galaxy
Nothing seen at 80 or 130x. Low in the light pollution of the southern sky though so not entirely a surprise.

Saturn Nebula
The brightest thing seen all night? Poor seeing, but Saturn shaped at 250x.

NGC 7006 and 6934
Two globs from the Caldwell catalogue which made little impression on me.

B142, B143 - Barnard's E
Caught in binos as an eerie dark hole in the sky. I felt there was some structure but I couldn't catch the E shape. I wonder if a rich field scope would do well here.

Cocoon Nebula
Quite tough I thought, with a hint of the dark structure like something caught in my eye. Missed Barnard 168 because I didn't learn of it until later...!

Pelican Nebula
24mm UHC. Ha ha, wow, that's definitely a pelican with a great big bright beak! Flowing upwards into...

North America Nebula
24mm UHC. Much brighter, with a lovely view of the Hudson Bay dark region, and a prominent dark lake below that I've only seen fleetingly previously. Stepping out for a wider view gives...

LDN 935 - NAN / Pelican Dark Nebula
Binos. The bright NAN and the much less bright Pelican below appearing as a single entity with a deep swathe of darkness in front. Back to the eyepiece and panning slowly down reveals...

Gamma Cygni Nebula
24mm UHC. I always see this as two somewhat bright parallel bands separated by a darker region. Panning further...

Sharpless 2-108 Nebula
24mm UHC. A bright region which filled most of the eyepiece led into...

Crescent Nebula
24mm UHC. The brain. But I was sure I also spotted a bright region alongside. I was sharing the eyepiece with the imagers and didn't spend much time on it, but I was so confident that it was there that I felt it didn't need confirming. Now, some images on t'internet show nothing in that location, whereas some show a bright region, but it doesn't really match and must surely be too faint anyway. I think this one caught me out, but I'm intrigued to know what caused me to be so sure there was something there.

B 144, Fish on a Platter
Just a small step further, a naked eye view of the prominent dark lane parallel to the Cygnus Rift. Binos revealed the broader dark region of B 144 although I couldn't see the reason for the nickname. Then a short hop to the side...

Veil Nebula
Always impressive, but this is the first time I've seen the famous photographic view. Absolutely, completely and utterly stupendous. The 24mm gave better views than the 14mm and the UHC was far better than the rather stingy dark offering from the Oiii. This is something I've found on every occasion I've viewed the Veil and I wonder why my experience is completely different to the conventional Veil/Oiii wisdom.

Pacman Nebula
24mm UHC. A bit of a hop across the sky. Mouth wide open ready to eat the stars.

Bubble Nebula
Another tough one. Difficult to be confident it was anything other than general ghosting around a star, but a second star in the same field of the same magnitude had no such ghosting so I think I saw it. No real structure seen and certainly no bubble. I wondered if I once saw a small shape like an animal claw but there was no consistency to it.

Cave Nebula
Various tricks, but saw nothing.

Spectacular views of both giant sweeping dust lanes in M31 and a spiral arm in M33 with the 14mm too. The Merope Nebula impressively filling much of the eyepiece although it's better seen in the wide field scope. The quality of these views again gets me wondering about failing on the Cave particularly.

Thanks for reading. Incidentally, this was earlier in the week. Oppressive grey skies are in charge again now.

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Cave=sh155... no, not done him yet either. You missed out on sh157 and 142 nearby and brighter to boot.

good to hear clear skies do still exist! Hoping for just a few at the end of the month! I find that imagers are quite friendly observing buddies, though they do sometimes create some light pollution.

 

cheers

 

peter

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49 minutes ago, cloudsweeper said:

Great report Paul - something for me to aim for!  I was delighted with NGCs 1432 and 1435, as well as vdb23 recently!

Doug.

Brilliant work Doug. That sounds like a cracking effort. I've been finding the glow in the Pleiades very tricky to pin down except around Merope. Must have a stunning sight.

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51 minutes ago, PeterW said:

Cave=sh155... no, not done him yet either. You missed out on sh157 and 142 nearby and brighter to boot.

good to hear clear skies do still exist! Hoping for just a few at the end of the month! I find that imagers are quite friendly observing buddies, though they do sometimes create some light pollution.

 

cheers

 

peter

Thanks Peter, those two look interesting. The list of things to see just keeps growing! Hope you get some good views yourself soon. These chaps were very considerate with their lights and it was fascinating to get a glimpse of a side of the hobby I've never seen before.

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Another cracker Paul, a great read.

Perhaps the OIII is better on the Veil under brighter skies? Your skies sound wonderful, so perhaps you don't need the more aggressive OIII to get the best contrast?

It would be interesting to know which @jetstream prefers?

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That's a beautiful report, Paul, and enjoyed reading it!  I'm encouraged by your description of the Bubble because I feel like I've failed to see it on previous occasions. But if you were to suggest did I see ghosting around the star where it should be located at, then I could agree I've seen it.  Tough one...  Nearby NGC7538 is much more obvious as a small nebulous patch.  Images of this entire region are remarkable.....if only our eyes could take it all in!  The telescope is actually delivering the view but our eyes are the limiting factor. 

What make is your OIII?  Just wondering if it is a Lumicron or Baader which are more severe than the Astronomik?  I find my Skywatcher UHC is more severe than my OIII.

Edited by Special K
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Great report !

I find both the O-III and the UHC (DGM NBP for me) work well on the Veil but the O-III gives a noticably more contrasty view through all my scopes, under my skies.

You don't have a Baader or Celestron O-III do you ?. I only ask because these two have very narrow band pass widths which might account for their "stingy" showing for you.

You do seem to be picking up objects that I find either not possible or very margninal with my 12" at home though so maybe Stu's point regarding the impact of these filters under dark skies is on the mark.

 

Edited by John
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Thanks everyone.

@John, @Stu and @Special K, interesting thoughts on the filters. I'm using a Skywatcher for both UHC and Oiii. Not too sure how these compare with the other brands you mention? When I bought them, I wasn't thinking much about how they compared with others at allowing/blocking different wavelengths with different efficiency, although I did avoid one (a UHC-something?) that sounded like a much less aggressive UHC. A year or so on I realise that every last scrap of contrast you can fish out of the sky helps! It would be interesting to know what others make of the different brands. Kevin, it's interesting that you say that the SW UHC seems more severe to you than the Astonomik Oiii? Even with variations in brands I wouldn't have expected a UHC to be more severe than an Oiii. Maybe there's a lot more variation than I realised. I don't want to appear dismissive of the SW Oiii by the way. For example, I'm keen to see Orion again in the coming months as I recall from last year that the Oiii fared very well with plenty of contrast around the main bright regions of M42 (and this alone means it has paid for itself!). It just doesn't seem to cut in on the Veil to my eye for some reason.

9 hours ago, John said:

You do seem to be picking up objects that I find either not possible or very margninal with my 12" at home though so maybe Stu's point regarding the impact of these filters under dark skies is on the mark.

John, you've got me thinking with this comment. Your experience is so much greater than mine that it needs consideration. I'm aware it's always a fine line when we're trying to see things on the limit of our kit and physiology, and I hope I've got a reasonable hit rate the right side of the line! I'm wondering if darker skies and/or a different pair of eyes could come into it too. I didn't check for the faintest star during this session, but I'd compare it as being noticeably better than several other sessions under NELM 6.2 to 6.3ish skies. I wonder if the sky was just super-transparent. During the other NELM 6.2-3 sessions, the Veil was lovely, but during this session it was simply astonishing. So extensive, with large areas that I'd never seen before that were just so obvious (and comparing later against images, it matched exactly). Back home (NELM 5.5 on a good night), I can get the brightest parts of the Veil and the NAN (both with filter), and just barely a hint of the main M31 dust lane if I'm lucky, but largely the extended faint targets simply aren't there. Some of the tiny faint galaxies are doable under high mag if they have a bright enough core though. Comparing those experiences, I'm wondering if it would have been around NELM 6.5 for this session, but it's only an estimate. At the time, I recall getting a bit frustrated star hopping which doesn't normally happen. Just too many stars in the finder! How does this compare with your skies/experience? In terms of the eyes, I think back to last winter... my daughter pointed up more or less straight past a streetlight at the Pleiades and said "Look! I've found a group of seven stars!". I wish I could see what she can see!

@FenlandPaul, go for it! I'm not usually in any hurry to cajole folks into spending on new kit, but a pair of filters has unlocked so many new regions of the sky for me. You've probably read elsewhere that the UHC is more versatile than an Oiii and that's my experience too. A UHC would be a solid first choice, but both are useful.

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wow that's a serious night catching nebulae! :)

I prefer the OIII for the North America, but possibly because my sky is brighter than yours. In any case, both filters are great and offer advantages.

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Paul, I think the skies you have access to are significantly better than most of us are able to observe under regularly. Home for me is normally around mag 4.5, mag 4.9 or around 19.05 best on my SQM-L meter. Observing in Devon, on the south coast I was at 20.5 which is mag 5.8 whilst I think Lucksall got to 21 at SGL10, which converts to around mag 6.1. These are all brighter than your site and we all know that  dark skies are the most important thing when it comes to faint objects like extended nebulae or galaxies.

I have used a SW OIII filter, but found the Lumicon was a significant improvement and worth the investment.

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Thanks Stu. I'd realised my skies were darker than average, but until reading your post I hadn't realised just how much difference there might be, with the great regular reports and talk of trips away, star parties etc. Sorry, it was rather naive of me.

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A lovely report with many interesting objects, some of which I have never seen. I was wondering how you managed the Veil with the moon like it was last night but found out as I read to the end. I must try the cave myself with the 18 inch, I spent a hour last night just looking at the blue snowball, I think I was pleased to have found it, very blue in the big scope even with the moon.

Alan

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On 10/7/2016 at 18:20, Size9Hex said:

 

Bubble Nebula
Another tough one. Difficult to be confident it was anything other than general ghosting around a star, but a second star in the same field of the same magnitude had no such ghosting so I think I saw it. No real structure seen and certainly no bubble. I wondered if I once saw a small shape like an animal claw but there was no consistency to it.

 

Keep trying for this one Paul, were you using your OIII filter? it really is quite apparent when you get the location fixed and compared to some of those tricky customers in your report certainly one of the brighter ones. Are you considering upgrading your filters, it is definitely a highly worth while investment to do so as quite clearly you have the appetite and have got the nebula hunting bug. Look forward to more reports.

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Dark sky turns a 10" Dob into a veritable photon Hoover!! You are outgunning my 16" under my NELM 5.5 home sky.

Lovely report. 

Could you see the Veil without any filters? That is when you know you 10" is really flying!

Paul

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On 10/10/2016 at 20:37, Paul73 said:

Dark sky turns a 10" Dob into a veritable photon Hoover!! You are outgunning my 16" under my NELM 5.5 home sky.

Lovely report. 

Could you see the Veil without any filters? That is when you know you 10" is really flying!

Paul

Thanks Paul. I'd hope you'd score a first round knockout against the 10" if they were side by side under the same sky! I'm about NELM 5.5 at home, and have been wondering what a giant dob could do with globs and open clusters. These seem to poke through the light pollution quite nicely and I really enjoy them as targets from home.

I had the UHC practically glued in place on this session, but I've seen it without difficulty without filters on a previous occasion (not from home, but from the dark site). I guess I hadn't realised until recently that getting to such skies regularly was unusual. :icon_redface:

On 10/10/2016 at 20:04, scarp15 said:

Keep trying for this one Paul, were you using your OIII filter? it really is quite apparent when you get the location fixed and compared to some of those tricky customers in your report certainly one of the brighter ones. Are you considering upgrading your filters, it is definitely a highly worth while investment to do so as quite clearly you have the appetite and have got the nebula hunting bug. Look forward to more reports.

Thanks for the encouragement Iain. Your own reports are stunning. Amazing what an even bigger scope can pull out of the darkness!

I was in a real muddle on the Bubble to be honest. I defaulted to the UHC and then wondered if maybe it was a reflection nebula so I took the filter off! Maybe it's another of those targets that becomes easier once you've seen it at least once.

I hadn't considered upgrading my filters, but the comments so far on the differences have got my interest! If I may, what are you using and how are you finding them?

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It is elusive but worth while seeking. When the transparency is very good, as you drift through that patch of sky just under a degree from M52, the Bubble is quite distinct. Here is a link as to what to expect, it can be frustrating as transparency varies, though as you point out, once seen you will know exactly what to look out for again.  

http://observing.skyhound.com/archives/oct/NGC_7635.html

My three deep sky filters are 2" Lumicon Paul, if you where to invest in just one high quality filter, I would suggest an Oxygen three Astronomik. They are expensive but as you value your time and make the effort to periodically get to dark sites, a filter such as this will receive considerable and constant use and without doubt provide very rewarding and memorable encounters. 

 

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