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View Full Version here: : Ngc6357 in the dewy moonlight - Now with Ha data


allan gould
30-06-2012, 11:11 AM
Tried out the QHY10 camera with my 5" apo last night and managed to incorporate a meridian flip to gather 4hr of 10 min subs on this nebula in Scorpius. It was quite faint however even with the moon quite bright in the sky I was amazed that I could get away with 10 minute subs. But it was wet, wet, wet last night and I had to turn the heater on in the observatory while I collected my darks and flats etc which dried things out a bit so in the morning things were not covered with moisture.
Stacked in DSS and processed in PS3. I must get to learn PI one of these days but my head is like a sieve and although I follow the tutorials I can never remember them in full.
Comments welcomed.


Ive now taken Paul Haese'suggestion and added some Ha data to the image which I think lifts it. Thanks Paul.
The Ha data comprises 10x10 min shots with QSI583wsg which had a horrendous gradient due to the moon almost on top of the object. Aligned with Registar and combined in PS3
First image RGB, second HaRGB
Comments welcomed as usual

RickS
30-06-2012, 12:46 PM
A good result considering the adverse conditions, Allan! I'm having a play with my data from last night now to see if I can salvage anything worthwhile...

peter_4059
30-06-2012, 12:46 PM
Sounds like you lasted longer than me Allan. It sure was wet last night. Can't seem to open your image for some reason?

silv
30-06-2012, 01:48 PM
this is a great picture!! beautiful!
even if it had been a moonless night!

congrats on your craftsmanship :thumbsup:

one question: why is it so orangish red?

allan gould
30-06-2012, 03:37 PM
Rick, Ill be interested to see your result

Peter, can you open the next one?


Guess the colour is what it is due to lots of H in the nebula. Ive reproduced it to tone down the colour a bit and tame the stars as well.

cybereye
01-07-2012, 09:35 AM
Allan,

The red colour is due to inter-stellar dust which is in between us and the nebula. Most of the green & blue channels have been absorbed - here's a link (http://www.aao.gov.au/images/captions/uks012.html) describing the phenomenon.

Cheers,
Mario

atalas
01-07-2012, 10:01 AM
Nice work Al.

allan gould
01-07-2012, 11:09 AM
Mario
I had a look mat your link and found that it was amazing that when they looked at their blue plates there was NO image of the nebula at all. So dust extinction was the answer and I stand corrected.


Thanks Louie. Hope to peruse your site when its up and going again.

Paul Haese
01-07-2012, 11:24 AM
This is a tough target Allan. It is mostly monochromatic in RGB but takes on a whole new light in NB. A good image of a mostly bland target.

If you want to talk about dew then come down to Clayton. Rarely is it dry there. Most nights the dew results in around 2mm in the rain gauge. Dew heaters are mandatory at at the very least hair dryers. The seeing though is good.

allan gould
01-07-2012, 02:47 PM
I may take you up on that as Im coming to Adelaide in September and if you can get Virgs into action could spend a night out. I was surprised it was sooo red but I'll try it in Ha and see what is there.

Ross G
02-07-2012, 06:05 AM
A very good photo Allan.

Nice composition and colour.

Ross.

allan gould
02-07-2012, 10:45 AM
Thanks for that Ross. Ive added some Ha data from last night which lifts it a bit. I've placed the image at the top.
Allan