Tuesday, November 15, 2011
NGC 7000, North America & Pelican Nebulae
North America and Pelican Nebulae area
in constellation Cygnus
Wide field image in HST-palette, from the emission of ionized elements,
R=Sulfur, G=Hydrogen and B=Oxygen. Note, the "noise" in background is not a noise but countless stars!
A cropped closeup to show the resolution. After countless tweaks, stars are now pinpoints from edge to edge, this lens is very sharp full open at f1.8 but focusing is more than difficult... the critrical focus zone is about 7 microns, 7/1000mm!
Canon EF 200mm f1.8 is a monster lens (fastest tele lens in the world). Total exposure time for all channels is just 4h 30min for this relative deep narrow band image, shot under a heavy light pollution.
As can be seen from the image, North America and Pelican Nebulae are actually a single emission area, divided visually to two parts by a dark nebula at front.
I have shot a narrower wide field shot from lower part of this formation, earlier in this Autumn, with a Tokina AT-X 300mm f2.8 camera lens, it can be seen HERE. Area is from just bellow the North America Nebula.
Image in Natural color palette from the emission of ionized elements,
R=Hydrogen + Sulfur, G=Oxygen and B=Oxygen + Hydrogen.
This palette is very close to a visual spectrum.
An animated image, with and without stars
Technical details:
Processing work flow:
Image acquisition, MaxiDL v5.07.
Stacked and calibrated in CCDStack2.
Deconvolution with a CCDStack2 Positive Constraint, 33 iterations, added at 50% weight
Levels, curves and color combine in PS CS3.
Optics, Canon EF 200mm camera lens at f1.8
Camera, QHY9
Guiding, Meade LX200 GPS 12" and a Lodestar guider
Image Scale, ~5 arcseconds/pixel
H-alpha 15x600s, Binned 1x1
O-III 6x600s, Binned 1x1
S-II 6x600s, Binned 1x1
Ps.
There is a tiny nebula in lower Right crner, near the "Pelican's head", if somebody knows, what it is, please leave a comment here.
It emits strongest at H-a but there are O-III and S-II bands visible too.
Update.
A friendly Blog follower just posted a comment about this nebula.
It's an emission nebula designated as a GN 20.43.9, thank you.
There is a tiny nebula in lower Right crner, near the "Pelican's head", if somebody knows, what it is, please leave a comment here.
Update.
A friendly Blog follower just posted a comment about this nebula.
It's an emission nebula designated as a GN 20.43.9, thank you.
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2 comments:
Great images!
The nebula is emmision nebula, a bright part of the Pelikan egde. It is designated as GN 20.43.9
Thanks!
I'll update this information in the blog post too.
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