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D850 Astrophotography Cocoon Nebula

Posted: 11 December 2022

Saturday afternoon, 10 December 2022, I was one of several local authors who participated in the "Oracle Authors Past and Present" event. I sold some copies of my autobiography.

Middle photo credit Jean Wilcox

Open: Saturday, 10 December 2022, 1806 MST
Temperature: 65°F
Session: 1812
Conditions: Clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" UHC filter
Focal Reducer


1812 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed Jupiter, then Saturn, 102X.

Next, prepared the D850 DSLR for imaging.

1824 MST: High Precision ON.

Slewed to IC5146 (Cocoon Nebula). It was faintly visible using averted vision, 102X.

Mounted the D850 DSLR at prime focus + focal reducer + UHC filter, focused on the star Deneb, and locked the 12" primary mirror.

Slewed back to IC5146.

1838 MST: StarLock ON.

After doing a couple of framing and exposure tests, took this StarLock autoguided, 5 minutes, ISO 6400, White Balance 4550K, image of IC5146 (Cocoon Nebula).


I removed the focal reducer and mounted the D850 DSLR at prime focus + UHC filter, refocused using the star Capella, and locked the mirror.

Did two framing and exposure tests and then took this StarLock autoguided, 10 minutes, ISO 6400, White Balance 4550K, image of NGC1333.


I plan to re-image NGC1333 on a future session without the UHC filter.

1925 MST: StarLock OFF.

The eastern sky was brightening from the rising waning gibbous Moon.

Viewed NGC1333 (nebula), 102X. It was some of the nebula was barely visible using averted vision.

Lastly, viewed Mars, 102X.

1936 MST: LX600 OFF.

Close: Saturday, 10 December 2022, 1950 MST
Temperature: 49°F
Session Length: 1h 44m
Conditions: Clear

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