Here’s my rendition of the famous Pelican Nebula, the Ha rich neighbor of NGC7000. It took four hours in 15-minute subframes to accomplish this decently clean and signal rich image.
2000 light-years away, it’s a very active star forming region.
Posts Tagged ‘PixInsight’
Pelican Nebula
Friday, October 14th, 2011Crescent nebula reprocessed for natural colors
Wednesday, October 5th, 2011
Here’s a humble attempt to reprocessing the Crescent I did with Gustaaf Prins and (waiting for clearance to disclose name). It’s a composition of red, green, blue, Ha, SII and OIII channels.
Of course when performing this kind of processing, there is usually no pretense of achieving real natural colors. The problems lies mostly in two factors: first, the Ha and SII channels are both reddish, while the OIII channel is greenish blue; second, the intensity of the signal at different bandwidths varies considerably, and if you don’t want to end up with a very color-unbalanced imaged, you need to stretch different channels differently.
This image uses red, Ha and SII (mixed in different percentages) for the red channel, green and OIII for the green channel, and blue, OIII and a pinch of Ha for the blue channel.
Wizard Nebula in H-Alpha
Sunday, October 2nd, 2011
Here are seven an a half hours, split in fifteen 30-minute subs, on the Wizard Nebula, aka NGC7380, aka Sh2-142.
NGC 7380 is a typical starforming region in the direction of an outer spiral arm of our galaxy (around 7,000 light years distant). This field contains many young energetic stars that make the natal gas that surround them glow an intense pink/red. The majority of stars for this newly formed group are out of the field to the upper left (right, in my image). Their winds and radiation sculpt clouds of gas and dust into the mountainous ridges seen here. The darkest parts of this image are foreground clouds of dust thick enough to extinct the light beyond them
(Quoted from http://www.noao.edu/outreach/aop/observers/n7380.html)
A quick gulf
Sunday, October 2nd, 2011
Only 100 minutes went into the capturing of this NGC7000, split into five 20-minute subs. Obviously this is an area extremely rich of hydrogen, as the amount of signal is incredible for my tiny 80mm refractor.
NGC7000, aka The North America nebula (obvious nickname), is a very large nebula, actually covering an area four times as large as the full moon. The area I imaged is called “Cygnus’s Wall”.
Very interesting, the shape you see is not the result of a particularly shaped cloud of gas, but it’s determined by the fact that between us and NGC7000 lie some bands of interstellar dark dust.
The distance of the nebula is not known, nor is the star that lights it. Some sources indicate that the star might be Daneb; in that case, NGC7000 might be 1800 light-years away, and it’s absolute size would be about 100 light-year across.
An International Crescent
Sunday, October 2nd, 2011
This image is the result of a cooperation between me, a Dutch astrophotographer named Gustaaf Prins and an Irish astrophotographer named (waiting for clearance to disclose name.)
I acquired the OIII and SII data, $NAME acquired the Ha, and Gustaaf Prins acquired the RGB (for the stars.)
Here’s the data:
SII: 13×900″ 12nm
Ha: coming soon
OIII: 7×1800″ 12nm
R: 9×300″ bin2
G: 9×300″ bin2
B: 9×300″ bin2
Equipment used:
SII and OIII: Skywatcher ED80, Moravian G2-1600
Ha: coming soon
RGB: TS APO Triplet 90/600mm, Atik 383L+
About NGC6888:
The Crescent Nebula (also known as NGC 6888, Caldwell 27, Sharpless 105) is an emission nebula in the constellation Cygnus, about 5000 light years away. It is formed by the fast stellar wind from the Wolf-Rayet star WR 136 (HD 192163) colliding with and energizing the slower moving wind ejected by the star when it became a red giant around 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The inward moving shock wave heats the stellar wind to X-ray-emitting temperatures.
Processing:
The image was entirely processed in PixInsight 1.7.
NGC7023, another take
Wednesday, September 21st, 2011
NGC7023
Finally I had a chance to do the Iris nebula again, this time properly. The first time I tried, the Moon was full and the sky was still slightly glowing of sunlight, because the Sun wasn’t 18 degrees below yet.
This time I managed 13 subs of 600 seconds, plus one sub of 420 seconds.
The blue part of the nebula is now clearly visible, and it extends well beyond the core that I managed to image previously.
Even some of the dark nebulae around it hint their existence, although very subtly.
They’d need more aperture, longer exposure times, and, of course darker skies.
Speaking of which, the sky was particularly dark last night, and I estimated a visual limiting magnitude of 5. The absence of the snow helps!
My old M27 with some borrowed H-Alpha
Tuesday, September 13th, 2011
Thanks to my friend Milosz, my M27 has been gifted with some twelve and a half hours of pretty good old h-alpha signal. I have here merged that data to my Red channel, and composed the image above with PixInsight.
M92
Tuesday, September 13th, 2011
M92
Here’s thirty-five five-minute shots at the M92 globular cluster in Hercules.
Messier 92 is about 26,700 light-years away and one of the brightest globular clusters of the northern hemisphere. It’s often overlooked, though, because of its proximity to the more prominent M13.
This is the first image flatted with my new light box. You can’t tell because this is a crop, but the box worked well.
Fireworks Galaxy and an unremarkable open cluster
Saturday, August 27th, 2011
NGC6946 and NGC6939
NGC6946, aka the Fireworks Galaxy, owes its fancy name to being the galaxy in which the largest number of supernovae have been recorded. And that’s nine. Unfortunately my picture doesn’t show any, but the galaxy is framed with the nice and bright open cluster NGC6939.
The Fireworks Galaxy is quite near, at only ten million light-years, but lies behind clouds of dark nebulae in our Milky Way, since it’s pretty much on the galactic plane.
Curiously, I haven’t found a lot about NGC6939 online; I suppose it means that it’s a rather unremarkable open cluster.
This image is a crop because I had trouble with my flat frames (I accidentally shifted the focus knob) and therefore you can see defects and artifacts on the full frame. The night wasn’t particularly transparent, and 3.6 hours of exposure proved to be barely enough to show the galactic core.
And when there’s so little data to work with, stretching the histogram to the limit will show defects that are beyond the extreme care I can take in calibrating the frames, such as the non uniform sensitivity of the CMOS chip.
The west coast of North America
Saturday, August 20th, 2011
NGC7000
Great news! I got my first CCD camera: a Moravian Instruments G2-1600. It’s got a Kaf-1603ME sensor, so it’s a very sensitive NABG camera. I got narrow band filters too, so expect some images in the Hubble palette.
The image you see in this post was shot through a 12nm O-III filter.
It depicts what is usually put on the left in images of the North America nebula, NGC 7000.
