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Old February 10th 09, 08:55 PM posted to alt.binaries.pictures.astro
Stefan Lilge
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Posts: 2,269
Default ASTRO: Sh2-168/9

Rick,

I'll have to put this one on my list. It has some nice structure.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
ster.com...
Yet another pair of Sharpless objects. I took this along with Sh2-152/3
back in 2007 a few nights apart. I had good flats for Sh2-152/3 but I
never took any for this object it appears. Least I can't find any that
match even somewhat and I had removed and reinstalled the camera between
the two. In doing so I somehow loosened a screw holding the green
filter in place. It was at an angle for this shot causing some
distortions to the green image which show up as green fringes. Also I
managed to not screw down the filter wheel itself and it was wobbling.
The red filter was well out of position from this. The result was a
mess. Think that's why I never processed either. I thought that 152/3
had the same problem. It didn't but this one sure did. I only used
pseudo flats to process this and it shows. The whole field is milky. I
also have a note in the file "Hazy conditions" so that is adding to the
problem. I'm not sure if the milky field is due to flats, haze, real or
some combination. I do need to retake this one. And I need to add
Halpha to the image.

Sh2-168 is the big and bright nebula at about 11,500 light years.
Sh2-169 is the extremely faint large red puff southeast of it (down and
to the left) with a bright blue star at its center. It is 5000 light
years distant so the two aren't related. At about 10 o'clock from 168
is a bright blue star with a lot of haze around it. It is just below a
rather bright yellow star. While much of the haze is glare from the
star some is due to the reflection nebula GN 23.51.5.01. I find no
distance for it. Down and a bit right as a much easier to see
reflection nebula around a much dimmer star. I can't find a thing on it
or a few other puffs seen around stars.

14" LX200R @ f/10, L=6x10' RGB=2x10', STL-11000XM, Paramount ME

Image displayed at 1.5" per pixel due to all the problems.

Rick
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