IC5146 – The Cocoon Nebula

[jase]

Hi All,
With the clouds slowly parting as the monsoon season draws to a close, I’ve managed to acquire a quick set of data to complete another image. So, without further delay, I’m pleased to present IC5146 – The Cocoon Nebula (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=160&fld_album_id=11)

About the target;
The Cocoon Nebula (IC5146) is located in the constellation Cygnus and resides 4,000 light years away. This remarkable nebula is intriguing in that it has emission, reflection and absorption characteristics due to dust particles in the region. The nebula is also a stellar nursery harbouring an open star cluster containing approximately 80 young stars in which some can be partly seen through the folds of nebulosity.

About the image;
The image is an [Ha+L]+LRGB composite consisting of 2.5 hours total (Ha:60min,RGB:30min respectively) taken from the Lightbuckets (http://www.lightbuckets.com) 24” RC (4876mm F/8), Rodeo – New Mexico. Four data sets were created: synthetic lum which was created from the RGB filtered images as I didn’t collect any luminance data on the rig, Ha, RGB ( w/ratio of 1.11:1.0:1.04) and a DDP stretch (hard stretched) RGB. Ha and lum placed through two iterations of deconvolution to handle the oversampling (.57 arcsec/pixel) and generally tighten the image. I created the synthetic lum to manage the Ha data integration considering the Ha data has very tight small stars, it’s difficult to match broadband filtered data. The synthetic luminance was blended in as lighten mode on top of the Ha layer in PS. Subtle adjustments were made to the opacity to bring it together. Not a huge amount of RGB data given the total integrated exposure times which made stretch the data hard. The synthetic luminance on the other hand was fine as I didn’t need to stretch the data too hard to being out the stellar profiles. The RGB data was put through neat image using layer masks to keep stars intact, but controlling noise. I found it complex to integrate the Ha data into the RGB. In most cases I’d blend 10% or so into the red channel, but the Cocoon is different target, one of which I’ve never handled before. As its part reflection, part emission, integration of Ha+R dominates the image. So I took a different approach by progressively blending the Ha data into the synthetic luminance. This process was performed three times, each time opacity was increased along with saturation so I could monitor both histogram and general aesthetics. I do however feel I lost some of the blue reflection nebulosity in the process. To circumvent this, I introduced another layer being the DDP stretched RGB. This layer was stretched rather hard, almost to the point of clipping, then heavily boosted in colour saturation. At the top of layer stack it was integrated as a soft light blend. As soft light is a darkening function, its important the data is stretched reasonably hard. I then altered the opacity looking for any form of data clipping in the RGB channels. – none present. Subtle selective contrast masking was performed to bring out the highlights and darken specific features, followed by minor colour balance tweaks to the shadows. Seasoned to taste. Don’t feel I managed the stars very well, but it works. A few internal reflection problems with the green filter due to a bright star off the edge of frame. I desaturated the area, but was not enthusiastic about chasing it due to a possible upset of the dusty regions.

Anyway until next time, Enjoy!:)

Cheers

[Dennis]

Hi Jase

Whilst I haven’t previously made a detailed study of this object, I cannot recollect ever seeing an image that generates so much of an apparent 3-D effect. I feel that I could simply fall into the soft clouds of nebulosity, to be cocooned in their enveloping cotton wool-like softness.:thumbsup:

Top stuff Jase – keep ‘em coming, although I’m somewhat pooped from reading about your exhaustive workflow and processing description; makes Ben Hur look quite un-epic like! :lol:

I’m still shaking my head at the 4876mm focal length….wow!:eyepop:

Cheers

Dennis

[dcalleja]

Jase
I really appreciate your detailed info on post processing. It really helps the rest of us.

Oh - and the image is brilliant by the way

[jase]

Thanks Dennis:thumbsup: Enjoy reading your poetic responses. I concur, it does look like a glorified cotton wool ball. The ha data while strong, doesn't contain much in the way of hard detail. Undoutedly due to the dusty and reflective properties of the area. This wasn't an easy one to process. I think it would look interesting in narrowband.:confuse3:Maybe an idea. Its well placed at the moment for northern hemisphere folks. The processing is rather standard with exception to Ha integration being an iterative LRGB process. The soft light blend may have boosted the saturation a little too high I feel, but if you google this target, you'll note that many other images have a "lollipop" feel to it. Need more data to bring out the expanse of the region overall - 2.5 hours is minimalistic. Thanks again for checking out the image and making comment.:)



Thanks Dan. :) Providing the processing info is no problem, I typically make notes as I go along so I know what I did and if it works, I know what to do again. The routine is not rigid or "mechanical". The decisions to do what and when is usually target based. Pleased you liked it.:thumbsup:

[Bassnut]

Exceptional image there Jase, on checking some other top efforts on the Cocoon, you have handled the processing very well, it beats them, and the blue nebulosity came out nicely. The Synthetc Lum looks natural too, the RGB quality was ample. Theres an overall softness about it, but better that than noise, its very clean.

A pleasure to view.

[Garyh]

I agree with Fred there!
Many images of this object seem overly red biased but you have bought out all the delicate hues in this one and keeping the colors soft and very natural.
Beautiful work Jase!

[beren]

:) Awesome image Jase, as always the work-flow commentary is great even though its beyond by grasp

[jase]

Cheers Fred. Appreciate your feedback. Just made some subtle adjustments, I probably should have given it 24 hours rest before I posted the image after processing. The more you look at it, the more you can see things which could perhaps been performed better. I'm happy the way the synthetic lum integrated actually. Something reasonably new to me. I've seen other imagers use it with mix results (or perhaps something else went wrong, so I should be judgemental). Thanks again.:)



Thanks Gary. Yes, I looked at some of the other work others have done on this target, but well after I had commenced the processing. I don't particularly like viewing other images before-hand as the mind starts playing games pushing you towards a biased view of what the object is suppose to look like. I prefer to simply let the processing take me there...thus creating a unique and personal impression. Thanks.:thumbsup:



Thanks Beren. Pleased you liked it. Don't worry about the processing blurp, its just for those who are interested - just enjoy the end product:thumbsup: Thanks for taking the time to view and make comment.

[avandonk]

Not bad Jase. I try to keep up with your sagas of the convolutions and deconvolutions used to tweak the image to your satisfaction. I will only say this once (sorry 'ello 'ello) this is fine for a narrow field but for wide fields we are limited as to what manipulations we can use to 'bring out detail' as it looks incongruous compared with the rest of the image. I know this is an unfair comment as we are not comparing like with like.

All the same though your image shows you cannot beat aperture and good data followed by intelligent processing and presentation.

Best image I have seen of this object. But I don't get out much:lol:

Bert

[jase]

Cheers Bert. Yes, wide fields and deconvolution don't always agree. Comes back to your arcsec/pixel sampling too. Though one thing I enjoy with wide fields is hybrid imaging - adding data from a longer focal length instrument to give the image depth. Here is an example (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=108&fld_album_id=11). TOA150 was used for deeper luminance. The FSQ was used for RGB and the overall wide field panorama. So you're not always limited by wide field imaging. I find it good to strike a balance between narrow and wide. Processing is different between the two, though there is still the foundation of knowing what you wish to convey through stretching etc. Thanks again for your comments. Much appreciated.:)

[rally]

A truly beautiful looking image Jase,

And a nice illustration of the fact that a good final image can also be a function of the skill, effort and black art of post processing.

I am always curious - how did you manage the G2V star in this one.
Even the selection process is something I will yet have to master.

Thanks for sharing.

Cheers

Rally

PS - for White Balance I mean

[gregbradley]

A sensational image Jase masterfully processed.

Greg.

[theodog]

Great image jase.
I like the dark dust detail -just a hint of reflectivity.
Well done.:D

[multiweb]

That's a great shot! :thumbsup: Reminds me a bit of the trifid.

[RB]

Another stunning image Jase !
The high res version is beautiful and I just love the blue hues of the wispy neb on the right up against the rosie Goliath of the Cocoon.

[sjastro]

Excellent image Jase.

Steven

[jase]

Cheers Rally.:) I'm pleased with the results considering the small quantity of data. Really, this target is best acquired through just a luminance - no Ha filtered data, hence I was rather dependant of the results of the synthetic lum to bring the reflection nebulosity through.

Good question, with G2V on rental scopes you typically go by the guidance of the rental operator. Many use Astrodon filters which are seen as easier considering their 1:1:1 colour balance ratios. Operators suggest using these "default" ratios to get you close to the right balance and it does, BUT if you're looking for greater accuracy you need to delve deeper. Rarely are the Astrodon filters a true 1:1:1 ratio on a given optical system. For this image, I didn't acquire any G2V subs, instead I referenced information from the SSRO-S/PROMPT (http://www.physics.unc.edu/%7Ereichart/prompt.html) team. They use a couple of 16" RCOS with Apogee U47's and Astrodon filters in Chile. The E2V CCD-47-10 AIMO back illuminated chip in the U47 has near identical spectral response to the Lightbuckets Apogee U42 that has the E2V CCD-42-40 Ceramic AIMO back illuminated chip. Their G2V tests reveal an RGB of 1.11:1.00:1.04 using SAO 163948 8.5 magnitude at altitude 75 degrees. I have also made an assumption that the optical coating between the two RCOS are similar. So there you go, no trickery to obtain these figures, just referenced existing information on hand. Again, thanks for taking the time to check out the image and make comment.:)



Thanks Greg. Much Appreciated.:D



Thanks Jeff. :) Indeed the dark dust in and around the main complex is interesting. There is a mass of reflection nebulosity around the key feature, however was difficult to extract without more data.



Thanks Marc. Pleased you liked it.:)



Cheers RB. Yeah, the faint reflection nebulosity adds an extra dimension to the image. The image characteristic reminds me of another image I worked on - The flaming star nebula (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=135&fld_album_id=11). Undoubtedly the pinkish hue on the Cocoon is due to much of the reflection nebulosity, compared to the more pronouced deep vibrant reds of Ha emission. Thanks again for checking and the image.:thumbsup:



Cheers Steven.:)

=====
Thanks to all those who have commented. I appreciate the acknowledgement.

[Alchemy]

Sure is tough at the top end of the imaging game, you know everyone is having a look with the fine toothed comb, but once again you have produced an image that is enjoyable to look at, i dont understand the fine details of the processing being a one shot color user, but the stars look good to me (not sure why you dont like them).:thumbsup:

[strongmanmike]

:clap:....amazing close up that! Very nice work with that lill'ol 24" Jase ;)

That was a nice short exposure and probably fairly affordable huh? Can't you please tell use the cost of taking it? Pleeeease? :sadeyes: Would be very useful info :shrug:

Mike

[Babalyon 5]

Great image and excellent processing. So, the average cost of the image is $400ish just for the 2.5 hrs? Wow!! :eyepop:

[rally]

Thanks for the G2V reference info Jase,

I was hoping it was going to be easier than that !

I'll store that away for later use !

Cheers

Rally

[jase]

Cheers Clive. Yes, but as you indicate when you use top end gear, you expect top end results. My goal is to be limited by the equipment, not my own skill in processing - simple. I wasn't too happy with the way I managed the stars. I use two options to manage the stellar profiles, DDP and/or Curves. DDP is great providing you don't sharpen in the process. The preferred is to use curves. In this case I used curves only and didn't feel comfortable that I maintained their profile. I try ensure there is a radial gradient to them so color integration is soft. Doesn't always work that way. Thanks again for your comments.



Cheers Mike. :D Yes, I enjoy the balance of working on both wide and narrow fields. The Cocoon suits both. I really like the vista of a wide field short of the region with the dust sweeping its way star field to the Cocoon. The up close and personal rendition presented here provides an interesting insight in this fascinating target. Certainly the first object I've acquired that has emission, reflective and absorption characteristics. Kind of cool to process too.

This image was well under $500. While more data would bring out the reflection nebulosity and cut down noise, its a good indication that when you've got aperture and serious sensitivity on your side, you don't need mega data (at high cost) to produce a pleasing result...just careful processing and some noise control techniques.



Thanks Babalyon. Pleased you liked it. I'm interested to know what people would expect to pay to access a 24" F/8 RC with premium CCD camera and dark skies to boot. When you put this cost into perspective. I've probably saved money instead of the fuel costs travelling to a dark sky site and food etc. Interesting perspective... Thanks again.:)



G2V is easy Rally. I've provided instructions on how I achieve the task a few times on these forums before - click here (http://www.iceinspace.com.au/forum/showpost.php?p=325375&postcount=8). Its not a difficult process, no different to learning how to drift align, auto guide or taking flats. Once you've done it a few times, you'll laugh at yourself when you realise how simple it is.;)

=====
Thanks All.:)

[strongmanmike]

What do you mean you haven't imaged the Trifid..?



I agree under $500 isn't anymore than a night or two in a Sydney City hotel I guess...:confuse3:Still, not sure how the trouble'n strife would compare them...or I...returning to the room after a nice meal and a few drinks :love2: ;)...Hmmm that'd take it well over $500 then too huh? :eyepop:...right! ponder, ponder, ponder......:whistle:

[Peter Ward]

Don't sweat it Mike...The prices are on light buckets' website. I signed up, but have not taken the plunge yet....yet given the weather of late in Sydney...could be tempted yet ! :)

But hey...'tis all relative....start my Airbus A380 course in October...$10k an hour should cover it ;)

[strongmanmike]

Oh yeh I know, I didn't sign up but I've had a look at the prices too, I was just interested in how much more the imaging extra's would add to the cost ie pointing, framing, focusing, filter changes etc..? and it seems they add significantly..ah see always hiden costs in everything :sadeyes:

Hope "you" don't have to pay for the A380 course? :eyepop:

Mike

[Peter Ward]

Streuth ! No way :) ! I think external customers pay around $70k but really have no idea about the real cost...as the dust is still settling......suffice to say, someone else is picking up he tab :)

[jase]

Does a wide field count (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=99&fld_album_id=11)? Not sure how much absorption the Trifid has however...The Lightbuckets 24" RC with U42 camera is 20'x20' FOV, this is exactly the size of the trifid! Would fill the entire frame.:confuse3:Could be onto something, but it would be pretty low from Rodeo, NM.


Well I thought I'd never live the day to hear that given the recent discussions.:whistle:

[avandonk]

What are you wasting your money on now? As I proudly showed them my new HA filter.

As they drive off in their $100k+ 4x4. Now worth $50K-. I felt very sad as they did not have a clue!

They did not even understand the rest. So how the hell can you justify a remote imaging system.

Just do what you can before it is too late.

Bert

[Peter Ward]

:lol: While I still do not for a millisecond consider rent-a-scope to be a clear reflection of what I can/can't do with an astronomical imaging system...a big Mac sometimes suffices when you need a few calories, with fries and a coke...(humm...cloud cover continues to increase...) make that in a hurry :)

[Ric]

A wonderful image jase.

I have not seen much of this nebula but the way the billowing clouds of nebulosity jump out at you is fantastic.

Cheers

[strongmanmike]

Sure does, that's a great image!




Maaaaate! there's heaps! see: http://tinyurl.com/2augtz (http://tinyurl.com/2augtz) :D



It'd be high enough ;) C'mon, whats another couple of nights accomodation in a Sydney hotel gunna matter? :whistle:

[marc4darkskies]

Knock out image there Jase!! :thumbsup::thumbsup:



Et tu, Brute!!!

.... and you already have a 14.5" RCOS !! :confuse2: :rofl:

Ah HA!! ... I have a plan!! :confuse3:To feed your soon to be acquired, aperture fever driven rent-a-scope habit, how about I give you a few thousand $$ - that'll be enough for at least a 3 night rent-a-scope fix and, in return, I'll take your piddly, second hand, rarely used, spider web ridden 14.5 off your hands and put it to work! :D You probably won't need that fading, outdated PME much longer either - Sell that & you'll get a couple more nights worth!!!:P:rofl:

Hey Jase - got any hardware for sale? ;)

Cheers, Marcus

[Peter Ward]

Yep....and I got the steak knife set! Complete with magnetic cloud bank!

[g__day]

I have a query with this. If I wanted to do the exact same thing as Jase - commercially do I :

1. book the scope same processing as Jase? or
2. am informed this has already been targeted with whatever parameters Jase used and offer to let me buy this from LB? or
3. As per point 2. but offer to let me buy this from Jase?

My point is Jase's shot is terrific (huge applause) but do LB own the data or does Jase and can they list what they have already imaged and offer to sell this for a reduced price?

[jase]

:lol: Sad, but true Bert...sad but true.



Thanks Ric! Much Appreciated.



Sorry Mike, not this time. M20 crosses the meridian at 33 degrees in Rodeo, NM. This is too low to do both the target and equipment any form of justice. I'll never say never, but its not on my target list for this year.



Thanks Marcus. :) Much appreciated.



Matt,

1.
Yes, you need to "book" the scope. Plan your target in TheSky or similar - its important to have the right geographic locales so you know when the object rises and to plan with FOV indicators so you can determine how you want frame the object. You'll need to select a guide star in this process or use the feature "guidelock" which rotates the PIR until a suitable guide star is found - this will negate any framing decisions you have planned however. When booking, unless you're really keen to use the scope immediately, use the "Best Available" or "Later" options. For "Best Available" they have an automated scheduling service that looks at the imaging plan to determine the best time to acquire the data, factoring in the weather, object elevation along with other scheduled plans. TIP: You'll receive further discounts using the Best available option as it allows the LightBuckets team to have visibility of the imaging schedules and to plan usage accordingly.

2.
It doesn't make any difference if the object has already been imaged by someone else...as such you are not informed of this. There is no sharing of data between customers - even of the same target. Each customer pays for the data they acquire and as such own it in entirety unless specifically agreed otherwise. For example, the Helix nebula (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=159&fld_album_id=11) image, I have no rights on the data. Alvin Jeng acquired the data and maintains full rights. I simply processed the data with his permission and was also granted permission to upload it on to my website providing due credit. If I was approached by someone to use the image for a specific purpose, I would need to engage Alvin to confirm permission for such activities. On the other hand, the M27 (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=154&fld_album_id=11) and IC5146 data (shown here), I own in entirety having paid for them.

Read their support section - http://www.lightbuckets.com/support.php
"Who legally owns the image data from my imaging plan run?
You own the copyrights to your image data. LightBuckets respects the intellectual property rights of others. We claim no ownership rights in any image contained in any of your photo albums and will not share your images unless instructed by you or otherwise required by law or permitted under a separate agreement with you. When you share a photo album, you allow the recipients of that album to share and make that album and the photos in it available to others. Please note that under the Terms of Use, you do agree to allow LightBuckets to use your images for promotional purposes on the Site. For more information see the applicable Terms of Use."
BTW, their Album references are associated to creating an Album on their site. You can do that to host some of the images you process, but I prefer to use my own site.

3.
I'm not willing to part with my data, but if you're looking to cut costs, why don't you distribute the cost between a few imagers. The group can decide on the target and one of you can set it all up, then distribute the data. I believe LB have group accounts for universities etc. Jump on their forum and post a few questions. Just a word of warning, don't expect "glamorous" images without work. If you've never processed individual R,G,B,Ha or luminance fits files before, you may wish to practice before you make the jump.

I hope this information clarifies your questions.

[g__day]

Jase,

Thanks for your replies - this level of operation I would guess is maybe two years away from my level of experience. If I wanted to fast path my learning - I'm sure a few weeks with a highly skilled astronomer would get me there, but given their scarcity and my time poor life that's unlikely to happen soon!

But yes I could see group collaborations - from funding through to set up and image processing.

On my earlier question - if a third party offered hosting and fee'd access to others images (at an agreed on price point) - this might make some sense if users could opt in to submit their data. If someone said to you donate the data and well pay you $50 every time some one wants it - you might end up ahead on a good image run. Similarily if someone said here are targets already imaged, with quality data at $50, $100, $200 etc price points versus a cost of $700 to do it your self - that would be a great option.

If I really want that image - I could offer to pay Peter to collect it using LB and you to process it etc. If I am only end result motivated I don't care how the magic is done nor the equipment used - only end results.

I ponder if LB will get a third party firm to offer a image data hosting and re-sale facility then allow another third party to offer image processing - they could well be a market for this.