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View Full Version here: : NGC 6992 "Veil portion" in Ha and OIII bi-colour


Paramount
31-08-2008, 08:55 PM
Hi all
Well according to the records August has been the wettest month on record and I can believe that. The weather was looking a bit more promising last night and following a suggestion from a fellow imager I had another go at NGC 6992 but this time I added some OIII data to it to make a bi-colour image. Luckily the sky stayed cloud free long enough to get 9x10 minutes unguided subframes for each channel. The seeing was poor due to very faint mist in the air later in the evening and the sky never got totally dark despite no moon being present. The subframes were dark subtracted (10 darks), then aligned and combined using median combine in Maxim DL and then the two resulting master frames were colour combined in Maxim DL using Ha for red and OIII for green. The resulting colour image was then processed in Photoshop CS2
I have enclosed the full widefield version as well as a cropped closeup
Thanks for looking and hoping for a better September
Best wishes
Gordon:)

Since posting this image I had a couple of suggestions about adding data to obtain a blue channel so I have tried two methods
1. Creating a synthetic blue channel from the red and green channels using Noel's tools in Photoshop CS2
2. Using existing OIII in the blue channel and creating an RGB image in Maxim DL and then processing it in Photoshop CS2
I have posted the images on my website http://www.imagingtheheavens.co.uk (http://www.imagingtheheavens.co.uk/) in the nebulae section of the image gallery along with the other images for comparison, I would be interested to know what people think

http://www.imagingtheheavens.co.uk/USERIMAGES/NGC6992colour.jpg

http://www.imagingtheheavens.co.uk/USERIMAGES/NGC6992colourcrop.jpg

Ric
31-08-2008, 11:21 PM
Wow, I like the contrast in the colours. The widefield has a real feel of depth to it.

Very nice indeed.

Bassnut
31-08-2008, 11:29 PM
Very nice indeed. Natch the pic res is trashed by the posted res Gordon, sigh, present so at ur peril, a shame.

Alchemy
01-09-2008, 05:58 AM
nice detail, as its a bicolor mapped image , the color balance isnt a concern, the closeup you provided.... what ratio is that cuurently displayed at? ..... can we go even closer? (we're a tough audience here)

iceman
01-09-2008, 06:14 AM
Like Ric, I love the striking colour contrast.

Nice work!

Paramount
01-09-2008, 06:35 AM
Hi
Thanks for the comments, I am not sure what ratio the enlargement is at, unfortunately the package I use for my website automatically shrinks images to 900x650 approx which is a hell of a lot smaller than the pixel count on the H36, at some point I may post some of my better images to a site where the native resolution is preserved
Best wishes
Gordon
:hi:

Phil
01-09-2008, 07:48 AM
Wow love the colour well done.
Phil