Hi All,
They’re few and far between, but I’m pleased to present my latest effort; IC1848 – The Soul Nebula.
The faint emission nebulae and overlapping open cluster of IC1848 resides in the constellation Cassiopeia. It is commonly known as the Soul or Baby nebulae, due to the nebulosity displaying the contours of what appears to be a foetus. The nebulae glows vibrantly red due to energised hydrogen. Present near the top of the foetus head is the bright nebulae IC1871, while the open cluster dots the foetus stomach. The nebulae is estimated as being 6,500 light years distant.
The image is an [LHa][RHa]GB composite.
About the image;
The final image is an [LHa][RHa]GB composite with a total exposure time of 5 hours (L:90min, Ha:60min, R:50min, G:50min, B:50min). The data was collected over a couple of nights due to bad weather. Beginning to understand the colour balance output of the Astrodon filters, but still not really comfortable with them. I like the clean R channel that comes with the Custom Scientific filter set. I feel the colour balance is quite accurate despite the complexities of integrating rich Ha data that attempts to throw the balance out. More data would have reduced the noise associated with the Ha data. The knots of dark nebulae contrast well with the red nebulosity. May reprocess using a few different methods given time.
Image Processing;
All light subs dark, flat and bias calibrated in MaximDL and registered in Registar. Combined in MaximDL using RC Sigma Reject. Luminance data pushed through two iterations of deconvolution using CCDSharp. The Ha data was not deconvoluted in order to maintain maximum nebulosity. Files converted to tiffs for PS work that follows;
The “super” luminance layer was created in PS using a blend of Ha 70% and luminance at 30% and initially stretched using DDP back in MaximDL. To avoid the typical salmon pink nebulosity when integrating Ha data I created a super R channel using the Ha data. The Ha data blended into the R channel at 40% which brought out the typical vibrant nebula emission line. This process was trial and error. A too strong blend resulted in major work rebalancing. The new R channel was then recombined with G and B channels to created a new [RHa]GB blend. While this process assisted in producing a rich nebula colour, it throws the star colour balance out significantly. To counter act this, I layered the base RGB (no Ha blending) composite using a layer mask to “bring back the stars”. This allows for a more aesthetic looking result. Chrominance data was stretched using shadow/highlights tool to obtain better control of colour saturation as the non-linear stretch was performed. All three layers, LHa, RHaGB and RGB (stars) were then combined and manipulated in PS. A nasty red gradient was present due to a poor flat field which needed some corrections, but overall the data was rather gradient free (sigh of relief). A couple of layer masks were also created – colour noise reduction and selective contrast enhancements (for details). Concluded with minor colour balance tweaks before flattening.
Thanks for looking! I hope you enjoy it.
As usual, all comments welcome.
Cheers
Last edited by jase; 28-10-2007 at 11:50 AM.
Reason: EDIT - Wrong image upload (not final release) - now updated
Beautiful work there. Also thanks for sharing the information on how you processed this wonderful image.
That tiny nebula to lower right is interesting. I wonder if it is related to, or separate from IC1848?
Scott
What a beautiful portrait of this fascinating region. The manifold curtains and folds in the nebula are exquisite and the stars - well, the stars are simply gorgeous; their range of colours and sharpness right across the entire frame are quite breathtaking.
In Cassiopeia? From South Gippsland? Sorry if I'm missing something here, jase. How low to the northern horizon? I couldn't locate in in the basic software I have available.
Bloody Hell, the processing procedure, in 17 years i might be able to come close to that, that is if i haven't carked by then, very nice image Jase supurb, in fact.
Excellent Jase. The work you put into colour balance has paid off. The nebulae looks natural (without being salmon or florecsent), and the stars, again a natural white.
In Cassiopeia? From South Gippsland? Sorry if I'm missing something here, jase. How low to the northern horizon? I couldn't locate in in the basic software I have available.
IC1848 is only 9 degrees below the horizon from South Gippsland. Maybe he is on a really, really tall hill
Seriously though, the mount listed does not match the mount from his observatory page, so I suspect it is a remote observatory, maybe this one in Alabama. The equipment matches.
Beautiful work there. Also thanks for sharing the information on how you processed this wonderful image.
That tiny nebula to lower right is interesting. I wonder if it is related to, or separate from IC1848?
Scott
Thanks Scott. The nebulosity in question is associated with IC1805 – the heart nebula. It is adjacent to IC1848. I’ve also obtained some data of the central region of IC1805, but its giving me grief in processing. Nasty blooms cut through too much detail. Thanks again.
Quote:
Originally Posted by Dennis
Hi Jase
What a beautiful portrait of this fascinating region. The manifold curtains and folds in the nebula are exquisite and the stars - well, the stars are simply gorgeous; their range of colours and sharpness right across the entire frame are quite breathtaking.
A superbly processed image – well done.
Cheers
Dennis
Cheers Dennis. The region is rather spectacular. My original intention was to frame both IC1848 and IC1805 in the one image, but I was intrigued by the shape of IC1848 so focused on this. Pleased you enjoyed it.
Quote:
Originally Posted by erick
In Cassiopeia? From South Gippsland? Sorry if I'm missing something here, jase. How low to the northern horizon? I couldn't locate in in the basic software I have available.
ps. a fascinating image, thank you!
Well spotted Erick, was waiting for someone to challenge me. My imaging goals are not limited to my equipment/location in South Gippsland. I acquired the image data/calibration frames using an internet controlled robotic telescope located at the pristine dark skies of New Mexico – http://global-rent-a-scope.com.
Quote:
Originally Posted by leon
Bloody Hell, the processing procedure, in 17 years i might be able to come close to that, that is if i haven't carked by then, very nice image Jase supurb, in fact.
Leon
Thanks Leon. I spent several hours processing this image trying to determine what works and how effective it is at displaying the data I wished to highlight to the audience. We all work hard at the telescope acquiring the data, so it’s only in our best interest to maximise the data’s potential through processing. To no surprise, I’m still learning the ropes in processing.
Quote:
Originally Posted by Alchemy
stunning job, but we expect that from you.
thanks for putting up the processing details ( for future reference if ever i get that far)
Cheers Alchemy. One that has no expectations will never be disappointed.
Quote:
Originally Posted by Tamtarn
That is an incredible image Jase.
Have never seen this nebula before, thanks for giving us the opportunity to see such a wonderful image.
Thanks Barb and David. Yes, the object is not well known in the southern hemisphere due to its northerly declination. Pleased you liked it.
Quote:
Originally Posted by Bassnut
Excellent Jase. The work you put into colour balance has paid off. The nebulae looks natural (without being salmon or florecsent), and the stars, again a natural white.
Cheers Fred. I have a version where I created the super R channel using the luminance data instead of Ha. This made it easier to balance colours, but I lost too much nebulosity. GRAS plug – points? Thanks again.
Quote:
Originally Posted by h0ughy
WELL DONE AND A FANTASTIC RESULT! I can see a unborn child in that image, or is that just my imagination?
Thanks Houghy. Finally an asterism that you don’t need to be intoxicated to visualise!
Quote:
Originally Posted by strongmanmike
Yes you have captured a nice ultra sound of an unborn child there, is it a boy or a girl? .
Ok I assume you can't see this from southern Victoria so I am assuming it was done using data purchased from the US? New Mexico Skies perhaps?
Nice job as usual, an enjoyable image
Mike
Cheers Mike. Yep, captured from New Mexico. After all, it’s not about where and how the data was captured. It’s what you do with the data that counts. I feel sure you’ll agree.
Quote:
Originally Posted by Ric
Fantastic Jase, another stunner from you.
wonderful effort.
Thanks Ric. Pleased you enjoyed it.
Quote:
Originally Posted by citivolus
IC1848 is only 9 degrees below the horizon from South Gippsland. Maybe he is on a really, really tall hill
Seriously though, the mount listed does not match the mount from his observatory page, so I suspect it is a remote observatory, maybe this one in Alabama. The equipment matches.
Eric
Yes a very very tall hill Eric. Nice detective work regarding the mount. The PME is a waste for a 530mm instrument. In fact, it’s also a waste for the Losmandy Titan. These mounts track/guide extremely well and are best suited to much longer focal lengths. For robotic operations, there is only one mount, the PME. However, having stated all this, its not about the equipment, its about the data you collect from it.
Quote:
Originally Posted by iceman
An incredible looking object, beautifully processed. Thanks jase for another remarkable image.
Thanks Mike. I try to push the boundaries and challenge myself. Was looking forward to attending the AIC2007 this year (was actually on this weekend). However, due to work commitments in Europe, I couldn't make it. Maybe next year I'll pick up a few new tricks.
Once again, thank you all for your kind words and appreciating the effort I put into this image.
Very nicely done Jase!!
I always enjoy your composition and your processing as the object always looks so natural and unprocessed!
I sign that it has been done so well!
I have always wanted to try a remote imaging session!
cheers Gary
Very nicely done Jase!!
I always enjoy your composition and your processing as the object always looks so natural and unprocessed!
I sign that it has been done so well!
I have always wanted to try a remote imaging session!
cheers Gary
Thanks for the comments Gary. The trick to colour management is to closely monitor colour saturation as you alter image brightness through curves/levels/etc. Any changes made to image brightness should be followed up with colour saturation tweaks. If you haven’t calibrated your monitored, I would highly recommend doing so – especially for gama. Also, don’t set the final black point too high, leaving some unused space. Raising the black point to create a very dark sky background sounds attractive to bring out contrasting nebulosity, but the sky is never inky black so it’s important to portray this. A better way of handling this is simply to increase the mid tones.
I highly recommend giving remote imaging a go. You “own” that data you collect - there are no royalties. The global rent a scope folks are pretty good value. You get access to instruments in both the northern and southern hemispheres so you can image what, when and how you want. So if its cloudy where you are, get online an image anyway. Thanks again.
Quote:
Originally Posted by Phil
great stuff Jase nice colour and veryvery sharp well done mate.
Phil
Cheers Phil. Other than deconvolution on the luminance channel, no other sharpening was performed (I turn off sharpening in DDP also). I’ve found that if you use high-pass overlay selective mask of around 5 pixels and highlight the features you want to emphasise, it looks like the image has been sharpened but in reality its simply contrast adjustments. This avoids the nasty looking crunchy stars. Some pretty cool stuff can be done in PS.
Quote:
Originally Posted by Rocket Boy
You've done a beautiful job on it Dr Jase.
As others have said, the colours are fantastic.
Well done.
BTW you can never be too sure with these Ultra Sounds, there could be twins in there hiding behind one another !
Excellent work mate !!
Thanks Andrew. Hope its not twins…it may end up doubling the processing workflow.
=======
As I mentioned in the original post, I had trouble with the red channel gradients (even after flats had been divided). These were a headache to deal with as the RGB combine resulted in a red cast dominating the background – very ugly. Attach are to before (left) and after/corrected (right) red channel images. To correct this I created a subtraction image in PS then subtracted it from the original using pixel math. This was rather “clunky” and time consuming, but delivered the desired result. I don’t know how others do it – if you think you’ve got a better way, then I’m all ears.
I hope you enjoy it.
in 17 years i might be able to come close to that, that is if i haven't carked by then, very nice image Jase supurb, in fact.
.
Thanks again.
I feel sure you’ll agree.
