28 hours of Helix

furgle (Adam) · #1 17-08-2016, 01:44 PM

I've already done the Helix Nebula in natural colour, so I've imaged it again in narrowband. Lots of H-alpha and Oxygen-III, but barely any Sulfur-II.

34x 1200s H-alpha 6nm
33x 1200s SII 6nm
17x 1200s OIII 6nm

Total exposure 28 hours.

Shot with a QSI 683-ws8 Camera @ -15° though a Skywatcher Black Diamond ED120 on an EQ8 mount

Larger resolution here

Retrograde (Pete) · #2 17-08-2016, 01:50 PM

Stunning!

Atmos (Colin) · #3 17-08-2016, 04:21 PM

Really nice Adam, you've manage to capture some of the fainter Ha areas nicely

h0ughy (David) · #4 17-08-2016, 04:31 PM

done a great job. obviously over that whole length of time the seeing would have been an issue. Stellar effort

willik (Willik) · #5 17-08-2016, 05:18 PM

I Like it very good shot
Martin

billdan (Bill) · #6 17-08-2016, 05:36 PM

Looks really good Adam, a lot of detail and nebulousness. The Helix is an object that needs many hours of exposure thrown at it and you have done just that.

My only suggestion would be to brighten up the sky background to reveal more of the outer shell.

Cheers
Bill

batema (Mark) · #7 17-08-2016, 07:36 PM

That is beautiful. Glorious colours.

Regulus (Trevor) · #8 18-08-2016, 06:21 PM

Oh, wow! That's a bit special.
Very well done - Trevor

Slawomir (Suavi) · #9 18-08-2016, 06:53 PM

Quality data and excellent result Adam

leon · #10 19-08-2016, 08:40 AM

Wow, that is just stunning,

Leon

gregbradley · #11 22-08-2016, 02:46 PM

A very nice Helix there Adam. I think though some noise control is needed as there is some red noise in the blue areas and the outer edges seem to have broken down and pixelated.

So the background is too dark and this is black clipping the outer edges of the Ha areas and a bit of the Ha red has sneaked through into the blue O3 areas. I would mask the Ha out of the inner blue region as there should be no Ha there.

Greg.

furgle (Adam) · #12 22-08-2016, 05:33 PM

Thanks for the feedback. At 6nm there was definitely "Ha" signal where the OIII core is, though it may have been nitrogen. I'm about to fly out to the US, but if I get time I'll post the Ha & OIII FITS to google drive and anyone can have a go at processing them.

furgle (Adam) · #13 23-08-2016, 08:14 PM

Here's the stacked FITS. I included the SII, but not much in there. Have at it if you like.

https://drive.google.com/file/d/0B4U...ew?usp=sharing