Saturn on the Horse's Nose

[cazza132]

Part of a mosaic project of the Milky Way and surrounds. Work in progress that started near the Gum Nebula. 85 panels done so far.
Canon 6D (full spectrum), Zeiss 135mm f2.0
4x3s, 4x8s, 4x30s & 4x90s at ISO3200, f2.5 for each panel.
Darks and flats applied. Astrotrac used for tracking.
Bit of a red cast to the dark-mid tones after jpeg conversion - having trouble with colour in photoshop atm. Taken too much from the base of the green channel maybe? Was lucky with the positioning of Saturn :) Feedback welcome.

https://www.flickr.com/photos/130830021@N02/18297661726/in/dateposted-public/

[rustigsmed]

awesome result.. 4x stacks per panel and 85 panels! sounds like a lot of stitching Troy!

[Joshua Bunn]

Top work Troy, that is stunning!

[strongmanmike]

Looking great Troy the final work should look rather epic...and finally someone else not afraid to show the real colour of excited hydrogen ie magenta! ;)

Mike

[LewisM]

Well Mike, Troy DID SAY:

Perhaps therein lies your problem too? :poke::scared3:

[strongmanmike]

Hey, I ain't got no problem, t'is all you red imaging sheep out there have ;)

:lol:

[Andy01]

wow! That looks awesome - well done and a testament to perseverence :)

[gregbradley]

Wow.

Greg.

[Meru]

Wow!! Looks great, 85 panels is very hard work. Your processing skills are excellent, what is your work flow?

[Bassnut]

wow, thats a monster image, so sharp, stars so small. Excellent hard core dedication!

[RickS]

Definitely a monster of a project with so many panels. Well done, and I look forward to the final mosaic!

[nebulosity.]

As already mentioned, this is a stunning shot. I too would love to hear your processing workflow as the result it excellent.

Cheers
Jo

[AstroJason]

Wow, yes that is brilliant Troy. The dark dust looks like it is really 3D. Top work!

[Rod771]

Yes, yes, yes! :thumbsup::thumbsup::thumbsup:

More please! :)

[andyc]

Wow, that's spectacular, massive! Very three-dimensional indeed.

[pluto]

That's amazing!
Great work!! :)

[theodog]

Stunning.:eyepop:

[cazza132]

Thanks for the kind words!

Processing workflow as follows:
- Convert all light frames, darks and flats to 16 bit tiff in DPP
- Stack 16 darks to stack mode 'mean' for 90s and 30s each in photoshop and subtract from all the lights of corresponding exposure (have set up a PS action for this that lessens the effect on lighter areas to prevent black spots)
- Stack flat frames to stack mode 'mean' in photoshop to create a master flat (which does need fine tuning from testing) and divide from all lights (also have an action for this)
- for each panel, align 16 images (4x3s, 4x8s, 4x30s and 4x90s) using PT Gui (some manual insertion of control point and correction of the misaligned ones is usually required). The output file is a 16 bit *.PSB file with 16 layers.
- for each exposure (4 layers), convert to smart object and set stack mode to 'median'. Save each exposure to file name with suffixes A, B, C and D for stacked 90s, 30s, 8s and 3s exposures.
- In Fitswork, open A, B, C and D tiff files. Add images to each other as follow: A+B, AB+C, ABC+D then ABCD+A. Adding A for the second times helps the files to handle the next step. Stretch the gamma to 3.02 then clip darks each colour to end of histogram curve. Output as 16 bit tiff.
- Align panels in PT Gui
- Open in photoshop and fine tune levels and gradients (probably the most tedious part)
- Open in photoshop to finish

Still a work in progress. Have some panels with stars not in perfect focus or gone wrong for other reasons. Coming up to the best time of year for field work with clear conditions here in SE QLD, so will need a bit more time on site :)

[Joshua Bunn]

Thanks for sharing your workflow Troy :thumbsup:

Josh

[Paul Haese]

Huge project Troy. Processing of the panels and the mosaic itself looks great in my opinion. Star colours are superb and I think spot on to what Dr David Malin has talked about recently in talks I have seen from him.

Looks too magenta to me but apparently that is wrong to some. I think the dust should have a brownish colour myself. Just my opinion though.

Still an awesome undertaking and I certainly admire what you have achieved so far. :thumbsup:

[cazza132]

Thanks for your feedback Paul!

The magenta in the Ha areas comes from the unfortunate side effect of heavy colour balance adjustment of raw files due to heavy red/pink colour cast. A part of my workflow I will need to investigate.

Seems to be some debate on what the real colour of Ha looks like. Using a clip in Ha filter in my full spectrum 6D, the response from the red pixels is overwhelmingly dominant, but there is some blue pixel response, so the end result is a deep red/burgundy rather than a magenta. or bold red. The blue response increases the deeper you go into infrared.

As far as how 656nm looks to the human eye, my 650nm IR and clip in 12nm Ha filters look deep red/burgundy to my eyes.

Here is a retouched version of the original that I posted with some colour adjustments.

[Retrograde]

Looks great.
I had a look at some of the other pics on your Flickr page too - some of the best wide-fields I've seen :eyepop:

[Stevec35]

Absolutely stunning stuff and 85 panels too - congratulations!

Steve

[multiweb]

Great timing. Love that kind of shot. :thumbsup::thumbsup::thumbsup:

[Meru]

Stunning, like the re-process. Cheers for sharing the workflow, I will PM you to ask about your thoughts on the AstroTrac ;)

[Paul Haese]

I agree, I like the latest version. Nice balance. :thumbsup:

[SkyViking]

Fantastic effort and result! One of the best widefields of this region IMO.

[N1]

I don't know (or care) much about AP, but for some reason I'm finding this image spectacularly good. It has that 3D feel about it that most (but not all) others lack. This isn't just a picture of some DSO, this is a picture of Space. :thumbsup: