View Single Post
  #3  
Old March 2nd 09, 05:59 PM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
external usenet poster
 
Posts: 3,085
Default ASTRO: NGC 6951 and the Integrated Flux Nebula

Even with lousy seeing (obvious in the image) and poor transparency (mag
4.5 skies rather than normal 6.5) it came through quite strongly. I did
know it was there and took 3 rounds of color instead of 2 but again,
that really wasn't necessary. Actually I find it amazing you saw it at
all from your location. I used to image from a much smaller town
(150,000 at the time) using film and had to use Lumicon's so called H
alpha absorption filter to get much of anything on film. So I had to
work with clusters and emission nebula in black and white when in town.
I could do color only from out of town. There I only had to drive 30
minutes for 6.5 skies but as I got older that routine got more and more
difficult. Also I was always forgetting something, even with a checklist.

So when I retired I moved to the north woods where civilization is many
miles away. Fortunately my wife prefers this life as well so it worked
out for both of us.

Rick


Stefan Lilge wrote:
Rick,

very good picture, amazing that you even got usable colour data for the flux
nebula.
Actually the flux nebula can be seen in my city version of NGC 6951, but
only with an extreme stretch of the image. I must have known that the nebula
was there, otherwise I would have removed the uneven background with an
artificial flat.

Stefan

"Rick Johnson" schrieb im Newsbeitrag
ster.com...

Normally the Integrated Flux Nebula is very faint and needs hours of
exposure time. For some reason most try to take it around M81 and M82
where it is quite faint. It is "very" bright around NGC 6951 yet no one
seems to try and pick it up here. For this image I used my normal 40
minutes of luminosity data, not the hours needed up by M81 and M82. I
did use 3 rather than my normal 2 frames of each color to help reduce
the noise in the color frames. Conditions were poor this night and I
meant to retake it but that never happened. I forgot about it for some
time. Turned out to be rather easy to process. Interesting galaxy in a
very nebulous field.

14" LX200R @ f/10, L=4x10' RGB=3x10', STL-11000XM, Paramount ME

Rick

--
Correct domain name is arvig and it is net not com. Prefix is correct.
Third character is a zero rather than a capital "Oh".