"Danilo Pivato" wrote in message
. ..
I hope you will appreciate the enclosed picture taken out from a mosaic
of 20 images in Hydrogen-Alpha of the heart of Cygnus: from gamma to
eta Cygnus: :
The 20 images for mosaic have been composed with a program of
graphic elaboration.
These the technical data of resumption:

Coordinates of the center mosaic AR: 20h 12m 03s e Dec: +37° 47' 20"
Apparent total size: : 7° 31' x 6° 18'
Lens: Pentax SDUFII 100mm f/4
Ccd SBIG ST-10XME
Field: 1,4° x 2,1°
Filter H-Alpha 6,3nm
Total time of exposu 120 hours
Exposure time for each frame: 30 minutes
Number of nights of work 28
Total frame: 240
Start date: 2009.08.28
End date: 2009.10.13
The site: Roma (Italy)

For me this is one of the most beautiful in the northern sky because
rich star clusters, dust and hydrogen gas.
With my best regards,

Danilo Pivato
www.danilopivato.com

Excellent, Danilo!
It isn't until "the big picture" is seen that you realise just how much
gas and dust there is in many areas of the sky. Far too many folk
image an object (eg the Crescent nebula) and use software to remove
all of the background, perhaps assuming it is noise or gradients.
Personally, I prefer to keep it in the image, if it is genuine emission.
Best,
--
Rob