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Old August 7th 07, 07:04 AM posted to alt.binaries.pictures.astro
Rick Johnson[_2_]
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Posts: 3,085
Default ASTRO: M27 in H-alpha

With the first clear night in ages I had to take something even if it
was only a couple days from full moon. So I put in the H-alpha filter
and went after M27. Unfortunately, I had been working on the set-up and
didn't get a set screw fully tight. That resulted in the camera being
at a slight angle to the image plane. The east and west side of the
image was way out of focus but the center, where M27 was was nice and
sharp. So I cropped out the fuzzy stuff. I tried making a color
version using RGB data from last fall but didn't like the result. I
will try again. In the meantime I'm posting the black and white
version. Even with the filter I had some fogging that cost me much of
the outer envelope I'd hoped to pick up. My background was about 20%
higher than normal so some moonlight was getting to me. Of course the
moon wasn't all that far from M27 at the time. If you really look hard
you can find the very blue central star but it is really faint.

14" LX200R @ f/10, 3x30 minutes in H-alpha, STL-11000XM, Paramount ME

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

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