Hi friends of the celestial wonders,
…this is gonna take some time to read,…guys
Let me present you my most recent result on a very fascinating planetary nebula, located in Cygnus.
Ngc 7008 is a gorgeous object for visual observation in a powerful telescope.
I used the 20“ dobsonian at high magnificiation and it reveals both, color and details to me.
So I decided to go for a considerable deep LRGB shot.
I was really very lucky this time, being spoiled with very decent seeing conditions in the very nigh I acquired luminance data.
Judging by the FWHM-values in the images I read 1.2 arc seconds. Judging by the eye (5“ TMB Apo f/9-high power) it was about 7-8/10.
Transparency was very cooperating as well, even though I saw some faint high athmospheric clouds wandering throuh a couple of my color frames…
As I started imaging 2 nights before luminance with RGB when seeing was less well, I did not want to exchange the setup in terms of utilizing the powermate barlow,…and of course 13m3 is not perfectly bright…so I just kept course and 2050mm primary focal length sustained.
We are looking at 70 minutes 1.2 hours luminance 1x1 binned; and 90 minutes 2x2 each color channel. ( 6 darks each)
Of course the telescope used fort his job was again my „big boy“, the 9“ f/9 TMB Apo.
Astroart4 served me well acquirering the data and for autoguiding.
Preprocessing was accomplished in Maxim dl, as well as alignment and sigma combined stacking. A wee bit of DDP finally.
Further preprocessing was done in CCD stack (deconvolution (pos contrain 3 times 40 iterations)), as well as registax.
PS CS2 and Pix Insight LE for postprocessing.
The „Fetus-Nebula“ is a fascinating object, as it holds a dark „amoeba-shape“ like cloud that is said to origin back ages ago when a seperate nova blew up that very region…good for us, as it gives much more contrast now…
Now go ahead and click „full size“.
You will find an interesting star field. It came to my attention when the first light frame was downloaded: do you notice? The field is split in two halfs…
The number of stars is not symmetrical in terms of densitiy. The PN lies exactly in the middle, deviding the field in two halfs.
Most likely there is a dust-cloud somewhere inbetween the PN and the CCD chip,…which happens to meet my expectations, as we look into the Cygnus-region, which is repleat with multiple dust-clouds…
I saw this in all frames, including the 2x2 binned RGB frames.
Now be encouraged to hit „enlarged crop“ please…cos’ I also want to navigate your attention to the nice narrow optical multiple star-systems at 7h00 very close to the bright yellowish star. For me as one of the „non-obstructed-apo-guys“ imaging with a „small“ optical system in comparison to the „huge light buckett“-people (don’t take that too seriously) it is most pleasing to find these little guys definitely split! Also at 12h00 is an extremly tight double-system,…and this is also indicated to be split…I have no exact data on these guys, but the distance cannot be much more than 1 arc second,…I believe it is below that…?
There are of course many more nice features in this object,…and also in the image, which makes me really very happy.
Take a look onto the region of the nebula at 11h00 on the egde of the nebula. There is small irregular shaped part which deserves to be noticed as well.
So, guys, I do hope you enjoy the „ride“!
Your comments are most appreciated.
http://www.stargazer-observatory.com/ngc7008.html
best wishes,
Dietmar
).
