Elephants Trunk RGB with 8 hours Ha added to it ; New Processing technique

[Catanonia]

Nice to have some clear skies last night and I took the chance to experiment a little with my processing. I picked IC 1396 the elephants trunk is it was at Zenith for much of the night and pretty clear from planes and satelites.

Guiding was good with the Skywatcher MN190 and the TSOAG so I setup 20min subs with 8nm Ha filter to get as many as I could.

Half way through before the flip, I took a couple of hours of RGB binned at 2x for 150 seconds to get the star colours and overall colour of the nebula.

In the end I ended up with 9 hours of Ha in 20 min subs and a couple of hours of RGB in 2 x bin mode.

Normally I would process the RGB and then combine the Ha, but this normally give the dreaded pinky nebulas we all try to avoid. So I thought I would try another technique I had in my head for sometime.

Using PixInsight, I calibrated everything and during the star alignment and combination for the red channel I added in the 9 hours of Ha (reduced by 1/2 to fit the binning mode) into the red channel. This gave me RHaGB 2xbin image.

I then processed the Ha as normal and added this to the RHaGB image as a luminance keeping everything at full size.

May sound a bit complicated but it seems to have worked a treat with a nice colours balance image with all the hours of Ha sub detail showing. I suppose the resulting image is

L(Ha) R Ha G B LOL

Well here is the full sized image

http://dl.dropbox.com/u/10801850/Astro%20Pictures/Large%20Files/IC%201396%20Elephants%20Trunk.jpg

I will definately try this method again as it is giving very pleasing results with the right colours (not pink) and the detail from the Ha long subs and a lovely smooth image (hardly any smoothing has been done)

I hope you like it.

Cat

[ashworthacca]

Wow, love the detail in this, love the star colours, love the smoothness......love everything. A cracker. Thanks for sharing.

The process that you went through does sound intriguing.

[ollypenrice]

Interesting treatment and sharp, smooth result. Very nice ideeed, no question. Lovely detais in the top of the trunk.

I don't think you are getting quite the star colour you'd get from adding the Ha to red in Blend Mode Lighten in Ps but I think you are proabably getting more out of the Ha layer.

Have you thought of this for restoring pure rgb star colour? Put the RGB image underneath the HaRGB. Blur the RGB to get the star colour spread into the stellar cores and increase the saturation. It will look 'orrible but fear not. Now select the top layer and select the stars using Noel or Martin B. Expand and feather the star selections keeping within the real boundary of the stars, not getting into the haloes.

Run the erasor over the image to remove the cores of the HaRGB stars.

I find that by being careful with the star selection and the feather I can get a bit of the pure RGB star colour back into the Ha-loaded image.

Olly

[shaunster]

Great result mate, looks awesome with little or no noise and just great detail showing through!

[Catanonia]

Thanks all, it is a new way of processing to me and good points Olly on the stars. Will look into that next time.

[MikeWilson]

Nice work Catanonia and thanks Olly for sharing your star colour trick

[Shibby]

Ooh that's a beauty, marvelous level of detail!

[Catanonia]

Thanks guys, wanted to add more RGB to it, but weather has been pants

[steppenwolf]

Very nice and detailed and the star colours are certainly starting to show through which is always an issue with the addition of Ha - excellent