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D7000 DSLR Imaging: Cocoon Nebula

Posted: 10 December 2014

The sky became overcast during my previous session in the observatory. Cloudy skies continued until 9 December.

Open: Tuesday, 9 December 2014, 1819 MST
Temperature: 64°F
Session: 754
Conditions: Mostly clear

1826 MST: quick look at Mars, 83X. Then slewed to Caldwell 19 (Cocoon Nebula), my imaging target for the night before the waning gibbous moon rose. A hint of nebulosity was visible at 83X. Then slewed to the star Deneb, which would be the focus test star. Added the Antares f/6.3 focal reducer and mounted the D7000 DSLR at prime focus of the 8" LX200-ACF using a Meade off-axis guider. Then did a focus test on Deneb using a Spike-A Bahtinov Mask.

Slewed to Caldwell 19 (IC5146) and found a faint guide star in the illuminated reticle eyepiece (with Rigel Systems PulsGuide). Did an unguided 1 minute, ISO 6400, framing test exposure, which was good. This is a cropped image from a guided 5 minute, ISO 6400, exposure, post-processed using Neat Image software to reduce digital noise:


1903 MST: completed imaging and removed the camera and focal reducer from the telescope. 1913 MST: clouds coming in from the south.

I then began a tour of some Carbon Stars as described in a recent Sky & Telescope article. U Cygni appeared orange-red at 83X. T Lyrae also appeared orange-red at 83X. Tried for UX Draconis and S Celphi but didn't see any obvious red stars in the eyepiece.

1933 MST: couldn't do any more Carbon Star viewing due to increasing cloud cover.

I also did some beta testing of a soon-to-be-released program during this session.

Close: Tuesday, 9 December 2014, 2015 MST
Temperature: 56°F

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