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View Full Version here: : NGC 6946 - The fireworks galaxy


Nicola
24-02-2011, 12:59 AM
Dear All,

last September I had one of the few chances last year to go under a clear sky, and I managed to shoot my first galaxy image with the QSI583wsg and the VISAC at f/9. You may find the integration details on my web page.

http://www.skymonsters.net/immagine.php?img=NGC6946.jpg

I look forward to get your criticisms, I need to learn a lot about imaging and processing galaxies.

Clear skies
Nicola

Octane
24-02-2011, 01:15 AM
Nicola,

There's definitely gorgeous star colours throughout.

I do think that you need several more curves and levels iterations masked to the galaxy to really make it stand out. Particularly the blues in the spiral arms.

There's good data there by the looks of things.

H

Fabiomax
24-02-2011, 01:43 AM
Nice Nicola, and quite good resolutions. I see just a little bit noise, (my monitor?)
Cheers,
Fabiomax

Nicola
24-02-2011, 09:53 AM
Hi Octane, thanks a lot for your comment. My total integration time was relatively limited so I don't really know if I can dig out anything more then that, but I'll give the blue channel a try.

Nicola
25-02-2011, 01:53 AM
Yes, it probably needed more integration time to reduce noise.

gregbradley
25-02-2011, 10:52 PM
That turned out quite well for your first galaxy image.

Overall very nice. You could crop the image to make the object centred.
A bit of noise but as you say more time would help that. There are techniques to reduce background noise though. But more data is always better than fancy Photoshopping.

The orange star is a bit oversaturated with colour otherwise the stars look good.

As you mention it would be hard to get anymore out of this one without more exposure time. Imaging with F9 and 8 inches of aperture
will mean patience and long exposures are needed.

Your setup is looking good.

Greg.

Nicola
27-02-2011, 09:06 PM
Thank you Greg for your detailed comment. I definetely need to stack more exposures, especially if I want to be able to stretch enough to see spiral arms better. I might go for working at bin 2x2 at f/9, I will never have in Italy a seeing which would make me exploit 0.67 arcsec/pixel anyway, and live bin 1x1 for when I use the focal reducer (f/6.3). What do you think about it?

gregbradley
28-02-2011, 05:42 PM
.65 arc sec setup is assuming 2 arc seeing (1/3rd sampling). So if your seeing is worse than 2 arc seconds (which is pretty good) then theoretically you should be no worse off.

I'd test the assumptions though to find out for sure.

Greg.