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Setting Moon, Orion Nebula,
Horsehead Nebula, Thor's Helmet

Posted: 5 December 2016

Thursday, 1 December 2016, dawned with cloudy skies. By evening the sky had mostly cleared when I left home to attend a meeting of the Oracle Dark Skies Committee. After I got back home and was ready to go out to the observatory, clouds had returned. Cloudy skies continued on Friday, 2 December. On Saturday, 3 December, I attended the International Dark-Sky Association (IDA) General Meeting in Tucson, Arizona.

Open: Sunday, 4 December 2016, 2133 MST
Temperature: 47°F
Session: 1051
Conditions: Clear

Equipment Used:
12" f/8 LX600 w/StarLock
Wired AutoStar II handset
2" 24mm UWA eyepiece

D7200 DSLR

2138 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed the setting Moon, low in the western sky, 102X. Some color refraction was visible due to the Moon's low altitude in the sky.

Mounted the D7200 DSLR at prime focus. 2146 MST: took this image of the Moon, 1/250sec, ISO 1600:


2200-2213 MST: Wi-Fi ON. Did some tests of the ScopeBoss iOS app for the developer. Wi-Fi OFF.

Slewed to Rigel. SYNCed the AutoStar on the star, focused using the Bahtinov Mask, and locked the focus. Then slewed the 12" telescope to M42 (Great Nebula in Orion). StarLock ON. Took a series of StarLock autoguided images at various exposure settings. This is a merge of 4 images (30 sec, ISO 3200, ISO 1600, and ISO 100; 10 sec ISO 100; White Balance Auto) using Photoshop:

Click or tap on image for larger version

By including the 10 sec, ISO 100 image in the merge I was able to bring out the Trapezium stars at the center.

Next, slewed to IC434 (Horsehead Nebula) and did a series of StarLock autoguided images. This is a (cropped) 10 minute, ISO 6400, White Balance 4000K, of the Horsehead Nebula:


The flare is from the star Sirius, well outside of the field-of-view. I decided to leave it in the image for the neat effect it adds.

The last imaging object for the night was NGC2359 (Thor's Helmet). It was still a little low in the southeastern sky but I decided to image it anyway. This is a (cropped) 10 minutes, ISO 6400, image:


2342 MST: done imaging. StarLock OFF, High Precision OFF. Viewed Thor's Helmet, 102X. Nice view. Then viewed M42 (Orion Nebula), 102X. Always a lovely view.

2354 MST: LX600 OFF.

Close: Monday, 5 December 2016, 0003 MST
Temperature: 46°F
Session Length: 2h 30m
Conditions: Clear

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