M 16 in narrowband with a slight twist

[RickS]

Taken from the light polluted inner suburbs of Brisbane, the Eagle Nebula in Hubble palette narrowband but with RGB stars instead of those horrible magenta things. This is my first attempt at a full narrowband image. I think it looks OK but I've thought that before and been wrong :)
Constructive criticism is appreciated :thumbsup:

Scope: Ceravolo C300 @ f/9 = 2760mm FL, Atlas focuser
Mount: AP900
Camera: U16M
Filters: Astrodon E series Gen 2 LRGB
Guiding: Lodestar / MMOAG
Image scale: 0.67 arcsec/pixel
Exposures: 32x900s Ha, 49x900s O3, 48x900s S2, 5x300s R, 5x300s G, 5x300s B (33.5 hours)

Larger version here:
http://rickstevenson.smugmug.com/Astro-Photography/2013-10/i-nHdWVTz/0/X3/M16_NB_RGB_v3ps-crop-med-X3.jpg

Close up crop here:
http://rickstevenson.smugmug.com/Astro-Photography/2013-10/i-BCDbCG4/0/X3/M16_NB_RGB_v3ps-crop2-med-X3.jpg

Cheers,
Rick.

[Bassnut]

Wow that's excellent for 1st go :thumbsup:

I like the whispy lightness, gives great 3d effect against the darker elements

[RickS]

Thanks, Fred! I thought you might be horrified by the stars :lol:

[tilbrook@rbe.ne]

That's pure magic Rick!:thumbsup:

A real triumph with RGB stars, the hours spent really shows.

Cheers,

Justin.

[Bassnut]

I am :P . You get away with it this time, just don't do that again ;)

[ozstronomer]

Great Image Rick, I do like it without the Magenta stars well done :thumbsup:

[Peter.M]

This image really does it for me! I love the eagle close up, my wide field renditions never do it justice.

[jjjnettie]

My only complaint is that I'd like to see more contrast around the Pillars. The finer detail kinda merges into the back ground.
Great photo though. :)

[naskies]

Sublime, Rick! The RGB stars are a nice twist indeed.

[gregbradley]

That is a truly superb image Rick. Holy cow, that is your first NB? As JJJ says contrast could be increased around the pillars which are after all the subject of the image. But wow, that is a fine image. Your mastering all this extremely quickly and the Ceravolo is a real gem of a scope.

Greg.

[Dennis]

Move over Hubble, Rick is the new narrowband king!:);)

Cheers

Dennis

[alpal]

Hi Rick,
Wow - that's a perfect picture - so much detail.
You're convincing me to go narrowband.
That's a nice touch - pasting those RGB stars in.
Why doesn't everyone do that?

cheers
Allan

[TimberLand]

If light pollution is giving you grief I would love to see how your beast goes setup at a dark site. I would offer my farm but I only have darkness to the south east and it is only a small farm.

WOW.

Justin.

[RickS]

Thanks, Justin!



I appreciate the first time waiver, Fred :D



Thanks, Geoff.



Thanks, Peter. I am enjoying the longer FL even though it's a lot more work.



Thanks, JJJ. I'll take a look at that. I always learn a lot from posting an image here.



Thanks, Dave. I appreciate your offline comments and assistance as well!



Thanks, Greg. It's my first three colour NB. I've played with a couple of Ha/OIII bi-colours. I'll have a tinker with the contrast and see if I can do something. The challenge is always to avoid unwanted side-effects!



Thanks, Dennis. I'm not sure I have any claims to royalty at this stage much less displacing Hubble, but I'm happy to have produced an image that looks halfway reasonable. If I look back at it in a years time and cringe then I guess that's a good thing too ;)

[strongmanmike]

Firstly, that's a LOT of exposure on such a bright object :eyepop: ...I think Freddo is having an impact on many of you :lol: don't know how you all fit them in :question: :fishing:, well I know how Fred does but you mate, amazing :thumbsup:

Now to the image...well I happen to like some magenta in the stars of a narrowband image :shrug: I think it can impart some impact and that original Hubble look, to me it can look good provided it is toned down from what is inevitably present in a first pass SIIHaOIII combine...having said that though, I also like no magenta in the stars too :D :lol: :thumbsup:

The image is really quite good and any alternatives like bringing some of the dynamic variation in the contrast across the image back and upping the colour variation and saturation would be just variations :shrug: sooo not worth commenting further on really :)

Very well done Rick :thumbsup:...I wonder if Jase will hammer you for imaging such a well imaged object (so well) with that amazing kit of yours :question: bet he doesn't :sadeyes: :lol:

Mike

[DavidTrap]

Great work Rick. I really like the RBG stars.

That list of topics you need to cover in your tute is getting longer and longer ;)

DT

[RobF]

I love it Rick. Stars feel right, contrast not overdone.
If I could get my NB colours to look like that I'd be a happy man :thumbsup:

I'd be interested in the rough PI workflow and colour blends you used actually if you get time or feel the inclination to share sometime. Easier said than done getting it so natural (as you know!)

[RickS]

Thanks, Allan. It did take a fair amount of experimentation to get the star transplant working in PixInsight. Perhaps it will be easier next time?



Thanks, Justin. I do get out to dark sites for a couple of nights once a month if the new moon weather is good. It's just nice to be able to do a bit of imaging at home and a bit more convenient.



Thanks, Mike. I really only got that much data because I was out chasing the dim parts of the Helix every night and needed something for the scope to do until the Helix rose out the the trees at 57 degrees elevation. It did pay off though - the data was a pleasure to work with.



Thanks, David. Might need to be an intensive week long course :lol:



Ta, Rob. I'll send you my processing notes. I think David is keen to have another PI sewing circle later in the year so we might get a chance to compare notes over a hot laptop :thumbsup:

[Shiraz]

Congrats Rick, that is a super image. nice smooth colour with fine detail - top shelf. Stars just drop in unobtrusively and look perfectly natural. Regards Ray

[John Hothersall]

That's a beautiful result, stars do fit in seemlessly like Ray says. The SII is blended very smoothly but I tend to have the SII as a much stronger presence dominating the outer parts, but as usual with NB art is a personal taste.

The longer fl Ceravolo option has given the pillars better edge and shadow detail and with the big sensor you get all the important bits in too.

John.

[RobF]

Thanks Rick. Interested in another knitting circle too. Worried I won't have much if anything new to contribute but, while you're coming ahead in leaps and bounds!

[DavidTrap]

You guys referring to a serious session of PI as a knitting or sewing circle will just give my wife something further to ridicule me about!:P

DT

[jase]

Great image Rick. Enjoyed the colour palette you've present. Rather different compared to the deep, more pronounced hues that others display. Stars are beautifully resolved. A real stunner. Well done.

[strongmanmike]

Julia Gillard is a keen knitter..I hear she has some time on her hands, perhaps she would be interested in PI too :question:

[RickS]

Thanks, Ray!



Thanks, John. I'll have to look more closely at some of your NB work! The scope and camera are a great combo for targets like this.



I'm sure you'll have some good stuff to share, Rob!



Hmmm... perhaps we need to call it a "convolution" :lol:



Thanks, Jase!

[RickS]

I heard she's a member of the Photoshop faction :P

[DavidTrap]

I do believe I laughed so hard at that I may have snorted!

DT

[Paul Haese]

Nice Rick, great detail and smooth image. The mega data made for a very smooth image without the look of applying smoothing. Keep doing mega data (being a padawan of Martin's theory of 20-30 hours minimum) it produces the best results. Not doing it is for people who are too lazy to capture the data.:P

I like the integration of the stars too. Excellent to see narrowband with natural star colour.

Keep it up.:thumbsup:

[RickS]

Thanks very much, Paul! It's not too bad collecting megadata for narrowband. At least I can do that from home. It certainly makes the processing easier...

[Stevec35]

Great result Rick! Certainly worth the time you spent on it.

Cheers

Steve

[astronobob]

Holy torledo batman, That is a towering result Rick, narrow band / rubber band, i dont care, knit one pearl two, what have ya, Id be elastic, i mean estactic about that, and yeah, diff ways to present NB but that sits really nice amoungst the smorgous board Rick, Top Shelf ! ! !

[RickS]

Thanks, Steve.



I'm glad you like it, Bob. Your comments always crack me up. Keep them coming :lol: :thumbsup:

[PRejto]

Really terrific. I quite like the RGB stars too...in my opinion much nicer than magenta.

Peter

[strongmanmike]

No offence Paul but where do you pull these arbitrary exposure figures from :shrug: I mean, it depends on the size of your scope, sensitivity of your camera and darkness of your sky amongst other things :rolleyes:...throwing around "20-30hrs" means zip in the big scheme of things really, taking really long exposures doesn't the guru Yoda make :rolleyes: :lol: imaging is imaging... enjoy it for what it is, every image is an image and just as important no matter if it is by the Pugh or the pleb :)

Mike

[RickS]

Thanks, Peter!



Mike,

I agree that it's not possible to find a magic number that applies to all imaging set ups, but I think it's part of the natural progression of imagers to go from a quick grab of anything that's in the sky to collecting data over two or more nights to produce a quality image. That's certainly the way I have gone. That might mean 10 hours for a bright galaxy or 40 hours for a narrowband planetary neb.

In the end we're all limited by shot noise and the same laws of Physics and it takes what it takes to grab an image of a certain image scale and quality.

I'm not sure exactly what I'm trying to say here so I'll shut up now :D I expect that Paul will have a robust reply when he gets around to it ;)

[strongmanmike]

Yeah, of course, I know this and it's effective keep at it mate. Hey, I collected 33hrs on the Helix back in 2009, transported my whole rig 40km out of Newcastle each night for 7 nights over about a two month period :scared:...so I know what it takes ;)....I just giggle at the fixation on arbitrary so called long expousre lengths plucked out of the air as if if you aren't doing this then it doesn't really count :rolleyes:... and that often appear to do very little for a lot of time expended :shrug:

Love your work :thumbsup:

Mike

[RickS]

Mike,

Shiraz/Ray did some calcs a while back to model the performance of his ICX694 and Newt and Naskies/Dave has just been doing something similar. Think I might get on the bandwagon as well and determine my sub length and number of exposures scientifically. Then if it doesn't work I'll go back to just making it up :P

I do agree that you have to take many of the rules of thumb with a grain of salt. The variations in object brightness, sky glow, QE, read noise, etc. are so great that you need to know your gear (either by the numbers or from long experience) and work appropriately.

Cheers,
Rick.

[gregbradley]

I agree. It really depends on the object's brightness, aperture, dark skies, Sensor QE and sampling, narrowband or not.

Generally I find galaxies need the longest exposure times.
Megadata has its own problems. Like sometimes needing different sets of flats if anything is moved in between a series. If the image does not work out (not all do) then you've lost a lot of time investment.

Greg.

[naskies]

I've been going through John Smith's calculations this past weekend:

http://www.hiddenloft.com/notes/SubExposures.pdf

Starizona's Ideal Exposure Calculator and PixInSight's CalculateSkyLimitedExposure use the same equations, though they don't appear to have implemented the exposure reduction factors (i.e. shoot half the duration of sky limited exposures).

I've been putting together a spreadsheet using my camera's actual empirical values to be able to quickly calculate optimal exposures for each channel based on the target object's brightness, local skies, plane/satellite frequency, sensor temperature, etc.

(Thanks to overscan calibration (http://www.iceinspace.com.au/forum/showthread.php?t=112592), I now only need to shoot a set of dark frames for one duration at each temperature and they scale very accurately.)

[Dennis]

Refreshing to see that you are still a man of the people Mike and that the romantic era of amateur astrophotography is still alive and thriving, despite your amazing set up and world class results.:)

Vote Mike for PM!:thumbsup:

Cheers

Dennis

[multiweb]

You're doing some great work with the Ceravolo Rick. Inspiring stuff. Makes me wanna try harder. :thumbsup:

[broca]

Nice work Rick!

[Joshua Bunn]

fantastic image Rick, the scope is working well for by the looks.

Josh

[RickS]

Especially true for those of us who don't have a permanent observatory, Greg. At best I only get a night or two at a dark site once a month and I'd hate to waste that limited time!



Vote Mike for President! We need to sort out the US first :lol:



Thanks very much, Marc.



Thanks, Steve.



Thanks, Josh. Still some tweaking needed but any noticeable deficiencies in the results are down to me :)

[Ross G]

A beautiful closeup photo Rick.

Amazing detail!

Ross.

[Tandum]

More yellow !!! :)

Good to see someone has a working filterwheel.

[RickS]

Thanks, Ross.



I just had a play with Bob Franke's modified Hubble colouring and it looks quite nice. Maybe time for one more repro?

Hope you get your wheel back soon, Robin!