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Old August 9th 10, 07:13 PM posted to alt.binaries.pictures.astro
Glen Youman
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Posts: 177
Default ASTRO: Eastern Veil with Atik 383

Love the detail - there is a three dimensional appearance to this
image.

On Sun, 8 Aug 2010 22:34:59 +0200, "Stefan Lilge"
wrote:

I spent four (short) nights for a total of 10 hours imaging time in the
first half of July on the eastern part of the cirrus nebula (NGC 6992/6995).
The larger chip of my (rather) new Atik 383 camera allowed for a larger
scale than previous attempts with my SXV-H9 camera.
Nights were very warm, one of them well above 20 degrees celsius, so I could
only cool the camera to -15 degrees that night. I didn't have darks for that
temperature (only for -20 deg), so I had to scale the darks, but scaled them
the wrong way (dividing the dark signal by 2 instead of multiplying with 2).
That error didn't seem to have much effect on the final image as the 8300
chip has a rather low dark current (but still benefits from darks, unlike
the SXV-H9, where using darks usually gives worse results than without
darks).

Taken from the middle of Berlin with a Skywatcher ED120 plus Skywatcher
0.85 reducer on a H-EQ5 Synscan mount. Atik 383 L+ camera with Baader Halpha
and OIII filters, 17x20 minutes Ha and 14x20 minutes OIII, combined to a
Ha:OIII:OIII.

http://ccd-astronomy.de/temp4/6992coloursmallneugut.jpg

Stefan