A quick peek at the Keyhole

Camelopardalis (Dunk) · #1 27-01-2018, 01:01 AM

Folks,

Just a brief encounter with the monumental Eta Carinae nebula last week here in Brisvegas. To date I've dabbled with some Ha but this is my first three colour narrowband image...with the grand total of a dozen 2 minute subs per channel.

Skywatcher Esprit 100 + ZWO ASI1600MM-Cool + Astronomik SII/Ha/OIII.

This object is tricky enough with RGB when we have reference data for the brightness of the channels, but in NB

especially around the bright Keyhole region, where it would be easy to be heavy handed with the contrast enhancement to the detriment of the rest of the image. Hmmm.

I hope to make more of an effort with this as it becomes better placed in the sky, maybe even a mosaic to frame it with a bit of background sky!

I'm certainly not professing to have got any of this right, so any/all suggestions/critique to improve technique welcomed, just be gentle

Cheers,
Dunk

Edit: added tweaked Keyhole crop

glend (Glen) · #2 27-01-2018, 03:36 AM

Nice image Dunk. What gain setting were you using? More subs i think.

Atmos (Colin) · #3 27-01-2018, 07:12 AM

It’s a nice big bright Nebula so a good one to start with for a tri-colour. You’re showing up the Nebulosity quite nicely

Ryderscope (Rodney) · #4 27-01-2018, 08:56 AM

That looks pretty good to me Dunk. Good resolution and the cropped image comes up well too.

Andy01 (Andy) · #5 27-01-2018, 09:03 AM

I'd say you're off to a flying start - imo NB imaging is a black art and the subtleties of colour palette / replacement of magenta stars / balancing luminosity of three channels take time to master.
That said Eta C is a nice big bright DSO to get started on - Well done!

Camelopardalis (Dunk) · #6 27-01-2018, 09:59 AM

Quote:

Originally Posted by glend

Nice image Dunk. What gain setting were you using? More subs i think.

Thanks Glen - gain 164 IIRC. Hopefully the weather will find some kindness so I can catch some more subs through the narrow letterbox of opportunity

Quote:

Originally Posted by Atmos

It’s a nice big bright Nebula so a good one to start with for a tri-colour. You’re showing up the Nebulosity quite nicely

Thanks Colin - yeah I figured it'd be a good object to get some data in all three channels. I've tinkered with bi-colour and blends, but...

Quote:

Originally Posted by Ryderscope

That looks pretty good to me Dunk. Good resolution and the cropped image comes up well too.

Thanks Rodney - was certainly a random night, but I've no doubt a more selective night might grant better resolution still.

Quote:

Originally Posted by Andy01

I'd say you're off to a flying start - imo NB imaging is a black art and the subtleties of colour palette / replacement of magenta stars / balancing luminosity of three channels take time to master.
That said Eta C is a nice big bright DSO to get started on - Well done!

Thanks Andy - was nice to get some good signal in all three channels, I think that really helps understand what is there. Still, very tricky... and having played with a few different channel renderings, I can understand why SHO is popular...seems to help bring out the contrast. I was surprised that the OIII data was so much sharper (by FWHM at least), but then it is the shortest wavelength...certainly meant I had to practice my star masks

RickS (Rick) · #7 27-01-2018, 10:58 AM

Looks good, Dunk. You've got a lot of subtle shades there.

JA · #8 27-01-2018, 11:13 AM

It's rockin mystic charm + some wonderful iridescent-like colours.

Good stuff Cam

Best
JA

Camelopardalis (Dunk) · #9 27-01-2018, 12:06 PM

Quote:

Originally Posted by RickS

Looks good, Dunk. You've got a lot of subtle shades there.

Thanks Rick, subtlety isn't a strength of mine

Quote:

Originally Posted by JA

It's rockin mystic charm + some wonderful iridescent-like colours.

Good stuff Cam

Thanks JA, it's certainly different than I've processed before

Amaranthus (Barry) · #10 27-01-2018, 01:32 PM

Simply lovely!

Next step, RGB stars...

Camelopardalis (Dunk) · #11 27-01-2018, 02:27 PM

Thanks Barry - steady as she goes

Thinking about it, I must have RGB stars lurking around somewhere...

RobC (Rob) · #12 28-01-2018, 12:00 PM

Well done Dunk. You are up there with the best of them. Speaks largely for your imaging rig and enhancement skills.

Cheers

Rob

Camelopardalis (Dunk) · #13 28-01-2018, 05:08 PM

Thanks Rob - could do with more data

strongmanmike (Michael) · #14 29-01-2018, 11:40 PM

Yeah, for a brief encounter, this is quite a good effort Dunk, it's a bright bugger and I like the colours, nice work

Mike

Camelopardalis (Dunk) · #15 30-01-2018, 08:47 AM

Thanks Mike - I’m waiting for the clouds to clear to get some more subs...I’ve been waiting almost two weeks