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glend
08-11-2016, 11:26 AM
This is my first attempt at Thor's Helmet (NGC 2359) in Canis Major, about 12,000 LYs away. Thor's Helmet is surprisingly rich is Oiii, not so much Ha as I expected, and very little Sii - for the time invested with my little scope.
The image here consists of: 36 x 300sec Ha subs. 30 x 300sec Oiii subs. So total integration time of 5.5 hours . Camera was the ASI1600MM-C running at -25C, Baader Ha and Oiii NB filters, and the scope was the TS Photoline APO 115mm, F7 (reduced to f5.5 for this sequence). Processed in DSS with Darks and Bias Frames, and layer colour processing and stretching was done in Photoshop CC 2017. This is an HOS pallet image, and yes it is green again due to the Oiii data overpowering the Ha. I need to run probably twice as much Ha to get any more impact. Note that the histrogram looks particularly small, and give the time invested I am sure one of my larger scopes would have been a better light bucket.

Astrobin full screen image here:

http://www.astrobin.com/full/271388/0/

Detail page here:
http://www.astrobin.com/271388/

Regulus
08-11-2016, 01:12 PM
Well done. The detail is there and it's just the colour that needs work. Although green and yellow stars have a rather pretty effect, if a bit un-natural :-)

Trev

glend
08-11-2016, 04:59 PM
Thanks Trevor, I have rebalanced the colour and have the new version on Astrobin now:

http://www.astrobin.com/full/271388/B/

Atmos
08-11-2016, 06:59 PM
Detail is really nice Glen!
FYI, getting more Ha subs will smooth out the Ha channel but it won't change the colour balance.

Placidus
09-11-2016, 08:11 AM
Nonstandard colour palettes are legitimate but can be confusing.

What I do like about this wide image is the demonstration of the extent of the nebula. We can see some extremely faint outer extensions that are often out of field.

Camelopardalis
09-11-2016, 10:37 AM
Nice one Glen :thumbsup: got to be happy with that, lots of extension there.

Regulus
10-11-2016, 09:45 PM
That new version is so much better Glen, because it gives the central object definition. It was too blended with the overall green cast.
Nicely done.

Trev