Carina Nebula

[JoelRed]

Hi All!

Long time lurker, first time poster! Thought I'd share with you my first real monochrome processed image!

I thought revisiting my favourite target, the Carina Nebula, would be a great place to start with the new mono processing. This image is presented in the Hubble SHO pallet and is the combination of around 5 nights worth of shooting over the course of December and January from my backyard in the inner north of Melbourne.

Mount: Sky-Watcher EQ6-R Pro
Telescope: Sky-Watcher Esprit 120ED Super APO
Camera: ZWO ASI2600MM Pro
Filters: Antlia 3nm Pro Ultra Narrowband

Hydrogen Alpha: 69 x 180s
Oxygen III: 46 x 180s
Sulphur II: 70 x 180s
9.25 hours integration

Full Res version here: https://astrob.in/full/p5qet1/0/

[AdamJL]

You should post more often :)

That's lovely! Just had a look at the full res image on Astrobin, and boy there is a LOT of detail there. Incredible work!
Almost identical setup to mine as well, so good to know what this camera/scope combo is capable of (I haven't used mine yet).

Nice work, and hope to see more from you.

[strongmanmike]

An excellent narrowband, wavelength ordered, emission line image of Eta and her nebula that Joel :thumbsup:

Mike

[gregbradley]

A super image. The sharpness is outstanding.

Greg.

[alpal]

Hi Joel,
that's one of the sharpest pictures I've seen of Eta.
I can see the finger of God clearly -
and I can just make out the Mystic Mountain Herbig-Haro jets.
https://www.hansonastronomy.com/keyhole-nebula

You must have had very good seeing and guiding accuracy.



cheers
Allan

[JA]

That's SUPERB Joel. The detail, contrast and colour are excellent :thumbsup:

Best
JA

[JoelRed]

Thank you! It certainly is a formidable combo, definitely my best image to date.



You are too kind! I was pretty brutal with culling images that weren't pinpoint sharp. Sorting them in APP really helped me weed out the imperfect subs.



Thank you!



Cheers! I'll try the keep up the same level of quality!

[AdamJL]

How much data did you throw out in the end?

[JoelRed]

That's a good question, I had a look back and calculated how many frames I rejected from the total number.

I really wanted the Ha in particular to be as crisp as I could get it, so that I could use it as a luminance layer.

There wasn't much variation in my Sii frames, hence the relatively low reject rate.

It's not to say that a significant amount of frames were unacceptable, I just really wanted the best frames only.


Reject rate
Ha: 52%
Oiii: 66%
Sii: 13%

[AdamJL]

Thanks for the info! So the 9.25 was total including rejections? Or was that after rejections (which means just under 18 hours of total data).
Amazing work

[JoelRed]

9.25hrs was after rejections. So yeah, 18hrs total time seems about right.

[Decimus]

Brilliant image of Eta Carinae, Joel - mesmerising!

Richard

[AdamJL]

I've been looking at this image again. Really remarkable. Noticed you mentioned Lefty's Astrophotography on your Astrobin link... that's what I'm using as the tutorial as well :) It's really helpful!

Any reason you kept the magenta stars in, btw? Would've been a quick thing to change with an inversion + SCNR.

[strongmanmike]

It's obviously a personal choice but I think leaving a little magenta/red in the stars of a narrowband image looks really good, I just like the look :shrug:...and probably because of the earlier HST images, when we first saw such a palette :)

Mike

[AdamJL]

Fair enough!

[JoelRed]

I appreciate the revisit of the image! :thanx:

Lefty’s is great place to start, covers a lot of ground and easy to understand. I also quite like Visible Dark’s and Galactic Hunter’s. I like to see different ways of doing things and adapt them to my own technique.

I did do the invert image and SCNR method to remove the magenta cast, however I wanted to keep a little bit of colour in them, so I only did SCNR with a strength of 0.5. Was just personal preference really.



Agree 100% :thumbsup:

[Andy01]

That's a nice image, ticks all the boxes, :thumbsup:

Might be wothwhile tinkering with your colour palettes for a more distinctive result as you go forward. :)

[matlud]

That is a great Carina Joel, very well done! Lovely detail, it was well worth the brutal culling 😀👏

[JoelRed]

Thanks Andy! Mono processing is still quite new to me, but I can already see how much more you can get out of an image.




Thanks Mat, I think so too!