Author Topic: NGC7023  (Read 4654 times)

Offline vol.patrick

  • Newcomer
  • Posts: 6
NGC7023
« on: 2014 April 24 22:45:30 »
Hi,

I took this photo on April, 9th, 2014, Moon visibility being 65%.

http://astrob.in/92520/0/

Imaging with a DSLR, I'am not happy with the background . Is it due to the Moon, or to my workflow ( or both)?. Can I do better?

Any comment or suggestion to improve my treatment will be appreciated.

Thanks

Patrick

« Last Edit: 2014 April 25 02:45:26 by vol.patrick »

Offline georg.viehoever

  • PTeam Member
  • PixInsight Jedi Master
  • ******
  • Posts: 2132
Re: NGC7023
« Reply #1 on: 2014 April 25 14:52:39 »
If you want others to try, you'll need to provide the fits or raw files.
Georg (6 inch Newton, unmodified Canon EOS40D+80D, unguided EQ5 mount)

Offline vol.patrick

  • Newcomer
  • Posts: 6
Re: NGC7023
« Reply #2 on: 2014 April 25 23:24:58 »
Here is the link to the FIT file from the stacking of 106 images of 180s.

https://dl.dropboxusercontent.com/u/86018302/RGB.fit

May be I should have posted it in the Challenge section of the forum?.

Many thanks

Patrick



Offline Nocturnal

  • PixInsight Jedi Council Member
  • *******
  • Posts: 2727
    • http://www.carpephoton.com
Re: NGC7023
« Reply #3 on: 2014 May 07 15:13:16 »
Hi,

looks like you did not flatten your image. Without that you'll have trouble creating an image that looks nice in the center and on the edges.
Best,

    Sander
---
Edge HD 1100
QHY-8 for imaging, IMG0H mono for guiding, video cameras for occulations
ASI224, QHY5L-IIc
HyperStar3
WO-M110ED+FR-III/TRF-2008
Takahashi EM-400
PIxInsight, DeepSkyStacker, PHD, Nebulosity

Offline Geoff

  • PixInsight Padawan
  • ****
  • Posts: 908
Re: NGC7023
« Reply #4 on: 2014 May 08 23:52:29 »
The nebula looks quite noisy--try more exposure. Also the colours are quite weak.  Try a saturation boost with curves after masking out the background.
Geoff
Don't panic! (Douglas Adams)
Astrobin page at http://www.astrobin.com/users/Geoff/
Webpage (under construction) http://geoffsastro.smugmug.com/

Offline TobiasLindemann

  • PixInsight Addict
  • ***
  • Posts: 126
    • Trackingstation
Re: NGC7023
« Reply #5 on: 2014 May 09 11:57:54 »
Hi Patrick,

I had a try on your image.
http://www.tracking-station.de/zeigl/IrisPatrick.jpg

Although your data is not perfekt, it is good enough to create a nice picture. But I think you should invest in a coma corrector. It is not expensive and makes the picture really more aesthetic.

My workflow:
- auto-STF with unlinked channels
- DBE (because of the dark clouds it is not easy - try to set the samples by hand in the dark regions)
- drag the little triangle of the STF to a HistogramTransformation process
because of the strong gradients the background is still to colourful
- make a rage mask to protect the mid-tones and the highlights
- open a CurvesTransformation and decrease the chrominance, to neutralize the background more
- invert the mask and increase the chrominance, to boost the colors in the nebular

Surely you can do more processing, but I hope it helps you a little bit.
Please feel free to ask, if you have any questions.

Greetings
Tobias



Offline vol.patrick

  • Newcomer
  • Posts: 6
Re: NGC7023
« Reply #6 on: 2014 May 18 11:56:35 »
Hi,
Thanks for your advices.
I'm sorry for the late answer, but I had been out of town for a while.

I just realized that in the DSLR RAW format préférences,

I had checked "Create RAW Bayer image...  RGB Image,
instead of "Create raw bayer CFA image.. Monochrome image".

I believe that caused  among other things the background to be colourful, specially in the red channel.
Anyway, I'll give it another try and apply your advices.

Thanks again

Patrick