IC 4685 - A Baby Octopus in Sagittarius

[Andy01]

Can you see the baby octopus with blue eyes staring at you?

IC 4685 is often overlooked by astrophotographers in favour of it's more famous neighbour, M8.
The signature dark river, (upper centre, B303) is very cool. :cool3:

When stars form, pandemonium reigns. Visible above are red glowing emission nebulas of hydrogen, blue reflection nebulas of dust, dark absorption nebulas of dust, and the stars that formed from them. The first massive stars formed from the dense gas will emit energetic light and winds that erode, fragment, and sculpt their birthplace. And then they explode. The resulting morass can be as beautiful as it is complex. After tens of millions of years, the dust boils away, the gas gets swept away, and all that is left is a naked open cluster of stars. (text- apod)

Very challenging to image from light pollutionville, I had to use several advanced PS masking and layering techniques to create this final image.
Might have finally put a decent sized band-aid on the tilt in the system as well ;)

Hope you enjoy the (edited) result! (https://www.astrobin.com/full/168h3a/C/)

Andy Campbell, Melbourne Australia, July 2020 :)

[multiweb]

Very cool shot. Beaute colors. :thumbsup: There is still a bit of funky stuff happening with your background stars but that must be processing induced.

[marc4darkskies]

Yep, an enjoyable image Andy but don't talk to me about tilt!! It's the bane of my existence! :mad2:

Colour & composition look great! I'm going to have to comment on the overly smooth look though. I think there could be some tonal detail missing in at least 1274 and 4685 and you've got a bit of noise in there too in the darker star fields. I hope that isn't being too picky - at low res it's a very pretty image. I'm basing my opinion on other renditions including my own (https://pbase.com/gailmarc/image/126063511/original) LRGB from 2010.

[Placidus]

Immediately saw the (blue-ringed) octopus. BigToe will never look the same again.

Superbly photographed.

Stay safe down there.

[LewisM]

That switch to Takahashi (FINALLY!) sure has done you well... :)

[Retrograde]

A very fine effort from such light-polluted skies.
This has all the punch that was missing from my recent DSLR effort & is a reminder of what to aspire to. Very cool.

[Ryderscope]

Fine work Andy. In lieu of on octopus I see a strange fish with a blue eye and a knobby jaw :)

[Andy01]

:thanx:

Cheers Marc, what can I say? One can only process out so much LP from class 6 Bortle skies :shrug:



Hey thanks Marcus - not making excuses but the detail is there on the Ha but when blending and looking for an image to "pop", some of it was masked by the red hue depending on how much luminosity is applied, it then became a compromise between gaseous appearance and hard detail, or aesthetics & science if you prefer.

However, at your suggestion, I've selectively re-layered the Ha back over the top as Lum, and it has made a significant difference in those regions - Thanks! :thanx: Edited Image (https://www.astrobin.com/full/168h3a/C/)

I also incorporated your critique from my last image - when you suggested using Lum to reduce noise - which helped enormously as I'm not under pristine dark skies here!
Anyway, I'm slowly learning to control Lp & working in HaLRGB so I'm pretty happy with this result from light pollutionville. :D

BTW, your image was in my top three when I pulled up reference images for processing this image! :lol:




Ha Ha, cheers Mike - thank my 11 y/o son for spotting octobaby first! :lol::lol::lol:



Cheers Lewis, almost there now :thumbsup: I've just learned of Testar in Sydney - they have an optical test bench & can re-collimate Taks if the entire lens cell is tilted, which is I suspect the case here.



Thanks very much for your encouragement Pete! I worked really hard on this one to get this result from my location - it's much better than my previous efforts - cheers :cheers:

[multiweb]

LP doesn't cause that. Noise reduction or color stretching. Repro looks a lot better in the fine details.

[Bart]

Very nice Andy, lovely rich colour and golden stars! :thumbsup:



Nearly as good as mine! :P;):rofl:

[pkinchington]

Good one Andy. I am trying to get some blue back into my eta carina shot - Your blue looks great.

Cheers Peter

[marc4darkskies]

Ah yes, nice! That looks much better Andy! :thumbsup: The detail definitely pops more now so the image as a whole is much more compelling! There's no doubt that when incorporating Ha as luminance, it's very tricky to get the best from both the Lum and the Ha data without one swamping the other. My version was straight LRGB so it was much easier to process.

BTW, anyone who skips doing Lum for a colour image - even under dark skies - is mad unless their camera is one of those magical ones which doesn't produce any dark current & readout noise!

One tip I'd also share more generally is look at your master stack for each channel separately. Properly aligned you can blink between them to see where your colour & luminance detail is coming from. EG: If you see good blue signal somewhere that's not in your processed colour image then you know you've done something wrong and you need to either find the error or work the blue data back in (probably via masking).

Anyway, I'm starting to ramble. Thanks for taking my critiques in the spirit they're given - trying to help!

[Peter Ward]

I have nothing meaningful to add, that has not been mentioned by other AP Sensei like Marcus.

It's a very good rendition. Nice one :thumbsup:

[Andy01]

Ha ha, Pareidolia rules again! :lol:



Cheers Bart, perhaps one day I'll get up to your image standards :lol::lol::lol:



Cheers Peter, was not easy but I got there eventually! :D



Thanks again Marcus, appreciate the constructive critique :thanx:



Thanks Peter :thumbsup:n- perhaps I should have entered it in the Malins, all my entries bombed this year! :sadeyes:

[PKay]

Inspiring image Andy

So much so, I have changed my (first light) target from M8 to IC4685 (It is in my small window between the trees).

Then I can use your image as a reference :-)

And I love octopus...

Good job!

[Slawomir]

Fantastic image Andy. I have always enjoyed your astro-images, but the last few in particular are a testimony of your skills as an outstanding astrophotographer. Please keep them coming :thumbsup:

Really really well done on nailing the optical alignment - something I am still fine-tuning myself.

[strongmanmike]

You should be very happy with that Andy, looks lovely:) .

Once again, it shows pretty clearly that good true colour shots can indeed be taken under big city skies. Hitting the brighter targets and utilising narrow band data to augment the RGB helps a lot of course. That said and certainly when it comes to fainter and more diffuse stuff like molecular dust and faint galaxy arms or outer halos etc, dark skies still rule :stargaze:.

Nice work.

Mike

[Andy01]

Cheers Peter, delighted to have inspired you with this little image :thumbsup:
Mmm Octopus :) I once accidentally caught one on a line at Kangaroo Island - huge one it was too! Froze it in milk and brought it back to Melbs where a greek buddy of mine taught me how to BBQ it, then dip into olive oil, soaked with oregano, garlic & lemon juice - Yummo!



Cheers Suavi, wish you were judging Astro photo comps! :lol:



Cheers Mike! Yes, I dream of dark sky imaging again :astron: - even pre Covid-19 I only managed a few trips way each year :sadeyes:
That said, thanks to good advice from the likes of yourself, Marcus, Peter W. etc I'm using this challenging time to lift my 'LRGB imaging under LP skies' game to a whole new level. :D

...and attempting to rectify my frustrating tilt issue! :shrug:

[rustigsmed]

nice one Andy, really like the colours on this one - good to see an rgb! you've done well considering it is from city skies.

[Cosmic]

Cool depiction of that dso. Colours look really nice here.

[Andy01]

Cheers Russell, LRGB from the 'burbs is always a good challenge, but I'm starting to get my head around it! :D
Thanks to a few good tips & suggestions here, the results are improving each time! ;)



Thanks Daniel, I worked really hard on them so I'm delighted that you enjoyed them too! :thumbsup:

[Atmos]

Nice colour and detail in the Ha Andy, well captured and processed. Still not sure where these clear skies are that you've been seeing :lol:

[gregbradley]

A wonderful image Andy. Your tricky processing paid dividends. I know how some images just fall into place and others need to be coaxed and pushed.

One comment and its not a defect but perhaps a way of enhancing the image further. I have seen some astrophotographers manage to get the golden stars to really pop and bring out the gold. I am not 100% sure how they do it, I presume its some combo of selective colour or other colour tools in Photoshop.

But if you can manage that it would be even better as these are stars after all and they are balls of fire.

Greg.

[codemonkey]

That's an absolute cracker, Andy. Love it! I'd been considering imaging this area too, but I finally got some galaxy imaging done instead... and I'm glad, this would be a really hard act to follow.

[Andy01]

Hey Colin, we had a run of 5-6 clear nights last week! Thanks for the nice feedback :thumbsup:



Goodness gracious Great Balls of Fire! :lol::lol::lol:
Thanks Greg, I'll keep that in mind on the next one :)



Cheers Lee - I was very happy with the results this time, using LUM as well as Ha for this really helped minimise the noise too. Looking forward to your next series of images! :thumbsup:

[Paul Haese]

It's a good attempt from the burbs and light polluted region and it would have been difficult undertaking the task of processing it. I know a lot of people have made very favourable remarks but there are something things with this image that I think need correction Andy. There appears to be a salmon look to the entire field and nebulosity. The outer star field should be golden in colour and the blue stars appear to be muted. On the high resolution and to some extent the native view on Astrobin there appears to be areas of speckle from sharpening or the use of decon, I am not sure which. Added to that what appears like over smoothed noise control (detail in IC1274 is almost non existent). Potentially a nice image but just some things letting it down.

[Andy01]

Rather than respond to yesterday evening's rude & condescending post by someone (not Paul) accusing me of deception. (It's since been removed) I'll instead respond to Paul's much more constructive criticism above :)

I've posted this comparison between our two versions of this object as a good example of the variance in outcomes,
driven by conditions. Paul's were taken under pristine dark skies and mine under heavy suburban LP. (I trust you're ok with this Paul?)
The original Ha data speaks for itself, the outcome, star colours etc. are dependant on how much Ha is contributing to the final image :)

[Paul Haese]

I don't have any objection but I think it is more than just the imaging conditions. Processing plays a very large part in my opinion.

I have included a 530 minute Ha I took of the region. No stretching just native process. It looks very similar to yours.

In my processing I chose to reduce the overwhelming effect of the Ha data on the end result. In the end I think I used an opacity of below 50%, simply because of the wash it was producing even in lighten mode.

Overall I have observed there appears to be a propensity for people to use the whole amount of the NB data in their images. This often skews the results with LHaOIIIRGB images and affects the way the object is portrayed. Ultimately this is dealers choice and just one of many observations among astrophotographers with experience.