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SpaceNoob
08-03-2015, 10:42 AM
Hi All,

Weather has been pretty horrible of late for imaging but here is a short (6hour) narrowband run on Eta Carinae and some surrounding nebula.

I am pretty happy with the end result considering the 0.44" image scale, high level thin cloud continually within field, 99% full moon, and relatively short integration time. :)

Eta is fairly blown out but I guess you get that with ~25k/e well depth and 1800 second subs.

Hopefully Autumn brings some clearer weather.

Image details:
Telescope: CDK 12.5 @f/8
Camera: SBIG STT-8300
Composition: Ha/Oiii(Ha)/Oiii, 6x 30min subs @ bin 1x1 per channel, all subs are sky limited (just).

Astrobin:
http://www.astrobin.com/full/161995/0/

Boosted slightly:
http://www.astrobin.com/full/161995/B/

Regards,

Chris.

marc4darkskies
08-03-2015, 11:37 AM
Very nice Chris! It has a bit of a monochromatic feel though. Personal taste perhaps, but I'd maintain the luminosity as is and push the colour to make it pop.

multiweb
08-03-2015, 11:43 AM
Wow! That is one superb shot. Stacks of details and the processing is spot on. One of the best close up if not the best this season so far. Love it! :thumbsup::thumbsup::thumbsup:

SpaceNoob
08-03-2015, 12:21 PM
Thanks Marcus,

I completely agree, boosting colour makes it pop a bit better. I just kept it toned down a bit to avoid my usual space disco but I think I went a bit far and the saturation was too low.

Here is slightly boosted:

Placidus
08-03-2015, 03:25 PM
Hi, Chris,

That is superb. Congrats on a lovely image.

Even as posted, it can withstand a surprising amount of wavelet sharpening to reveal more detail, most particulary in the two HH jets at around 55% of the way toward 3:30pm. (The sharpening would have to be done before setting the black point, or the dust goes to black). Possibly more deconvolution earlier on might also be possible.

Mike

Peter Ward
08-03-2015, 03:57 PM
What a delightful result!

Excellent :thumbsup::thumbsup:

RickS
08-03-2015, 04:38 PM
Well done, Chris!

SpaceNoob
08-03-2015, 05:20 PM
Thanks :)



Thanks Mike,

I avoided the deconvolution routines mostly because I can't really seem to get a handle on them and they were trashing it, or the beer I was drinking during processing was impacting my abilities. I did a slight unsharp mask at relatively large scale as this tends not to introduce significant artifacts. I applied a mask over the brighter stars to avoid enhancing any halos/smearing generated by oversampling and A/O. To further help I have rejected any subs that were registering above say 2.3 arc seconds, although I have probably 12 of each channel, the end result was only 6 each within this criteria. The range is 1.45 - 2.25 arc seconds, mostly the Ha were rejected as there was high level cloud present.

You can probably push the data still because I haven't significantly constrained the black point, the data was fairly noise free so I could leave the histogram slightly relaxed at the frontal edge to reveal some of the fainter structures.

May or may not be interesting, but the Oiii subs clearly reveal a very obvious peanut shape (though saturated) where I imagine the Homunculus nebula resides.



Thanks Peter, the field seems rather dwarfed by your latest achievement in this region! At 2.5m focal length with the 8300, I'm feeling a bit like a racehorse with the blinkers on, or perhaps a blind race horse given the perceived system sensitivity.

multiweb
08-03-2015, 06:06 PM
What makes this picture truly exceptional is the amount of fine details. The fact that you didn't alter the fine features during processing shows that good data doesn't need to be enhanced. There is a big difference processing close up shots with a high sampling and wide field images with less features. I reckon you've nailed this one just right.

DJT
08-03-2015, 06:13 PM
Hi Chris,
What a great image. The detail is excellent and the boosted version is quite something. Top job!

Regulus
08-03-2015, 07:17 PM
Lovely, lovely photo Chris.
Liking both presentations and cannot chose between them.
(hope u don't mind but, using these as a desktop for the next week, - say if it's not ok tho)

Trev

pluto
08-03-2015, 07:47 PM
This is incredible! Great work!! :)

alpal
09-03-2015, 08:13 AM
Hi Chris,
that has the extraordinary detail that you expect from a premium optic at long FL.
I would have boosted the colour even more with LAB mode but that's just me.

cheers
Allan

SpaceNoob
09-03-2015, 10:21 AM
Thank you, I'll probably add more things as I learn more about processing but for now this is about the limit for me.



Thank you :)



Thanks Trev, feel free to use the image! I have better formats that are less compressed if you would like, just PM me.



Thank you :)



Thanks Allan,

The optics appear to be functioning pretty well :)

Colour isn't one of my strong points, I am colour blind so I have to keep within limits or my bias will significantly screw the reds lol. I don't use Photoshop a whole lot, I am assuming LAB mode is a Photoshop feature?

Most colour tools I tend to avoid, else I end up creating something hideous but I'm keen to try :lol:

strongmanmike
09-03-2015, 12:38 PM
Yep Chris, a great Keyhole indeed, not much to say other than, yes, while you could have a go at making it pop more and giving it zip and Kapow factor (what ever that is :question:) :lol:..it isn't totally necessary, it is a nicely worked image as is, well done :thumbsup:

Mike

alpal
09-03-2015, 02:41 PM
Hi Chris,
Louie has a great short video on LAB mode here:
https://www.youtube.com/watch?v=fE2GS_87Ct8

If you want I'll boost it for you & post the result on Astrobin in the not public listing
& post a link here?
It would only take me 2 minutes.

cheers
Allan

Rod771
09-03-2015, 09:39 PM
Wonderful image Chris!

Lots of detail with a soft appearance, very real and natural. Well done! :thumbsup::thumbsup::thumbsup: