ngc 2392 9"f/18 !!!

[stargazer_7000]

hey - what is that? luminance only...? no color...?

well,
this is a result of an experiment I conducted last night when seeing
was really very good for a short periode.
I used a monochromatic demo-CCD SXVF H36, my 9" TMB apo but this time
@ f/18 !
I slammed in the 2" 2* big barlow cos I wanted to see, if the system
is powerful enough to allow imaging bright small planetary nebulas -
which shall become one of my future tasks,...I hope.

singel frames were only 4 minutes 'short' and it worked nicely!
the backgroundsingal shows a very comfortable low noise at 0°celsius
ambient. even though the chip is a engen.grade type artefacts are
negligable and are easy to handle.
I also took rgb files, but in primary focus at f/9.
today when preprocessing the data the bad news came along:

after completing luminance and r,g,b seperatly I wanted to registar
and align these 2 master-frames.
but - no chance to do so! no software I used was able to stack these
two successfully!

I really did not expect this in the fist place.

I often use f/9 data and combine it with f/7 data, when I use my
reducer/flattener.

but obviously there is a big difference in what happens to the field
when trying to combine f/9 and f/18...
I would have had to crop the image so dramatically that I refused to
do so,...cos it would have been to embarrassing...

frankly, it is embarrassing enough when I admit this luminance image
you see in the full size is already a 50% crop, as my f/9 system
illuminantes the chip nicely, but fails to cast nice round stars onto
the chip all over the area.
what waste of pixels...!

so - I N E E D a decent flattener for my 9" TMB Apo f/9.
(and one is already on its way...)

in future when imaging with the barlow, which I will continue, I'll
have to do my r,g,b files also with the barlow lenses...will be
intersting to see if this works at a reasonalbe amount of exposure
time...?

data:
8.1.08:
9" f/18 (TV 2" 2* big barlow)
SXVF H36 (50% crop)
18x4 minutes single frams
7 darkframes

image acquisition: AA4
preprocessing (dark-calibration, kernel filtering, alignment,
stacking and Deconv. in maxim dl)
pre-sharpening in CCD sharp. DDP in Maxim DL.
postprocessing in PS CS2.

full size (crop) can be found here:
http://www.stargazer-observatory.com/2392-full-L.html

an enlarged crop is here:
http://www.stargazer-observatory.com...nl-crop-L.html

thanks for looking,

Dietmar

[RickJ]

Now that's a fantastic shot. I get seeing like that for 1/10th of a second but never for even 2" let alone 4 minutes. Guess I need to move to Austria.

Rick

[andyschlei]

That's a great shot. Just beautiful.

[stargazer_7000]

thanks Rick and Andy!
Rick you're welcome anytime... don't forget to bring your skies along...

[winensky]

That is a fantastic shot. The clarity is astonishing. This little fellow is not an option for us down here but this little experiment has encourged me to try my barlow on the Blue Planetary and some of the small bright emission nebulae in the LMC.

Kind regards
Matt

[stargazer_7000]

hi Matt,

thanks! and - go for the barlow experiment!

[JAICOA]

Hi Diets, what a beaut! It's amazing with very beautiful structures. and Congrats With this Photo being selected Editors choice at Sky and Telescope Clear Skies

[Kyle Edwards]

That is amazing, it is one of the best amateur images of this object I have seen.

[stargazer_7000]

...thanks a lot Efrain and Kyle.
Efrain, also thanks for noticing this...

[NGCHunter]

That's insanely good. I know a 9" APO is nothing to sneeze at, but geez, that exceeded my expectations of what's possible.