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Triple Conjunction,
Orion Nebula UHC HA Filters

Posted: 10 January 2021

Wednesday, 6 January 2021, began clear but clouds arrived during the afternoon, with an overcast sky that night. Cloudy skies continued until Saturday, 9 January.

1816 MST: took this photograph of the "triple conjunction" of Jupiter-Saturn-Mercury using the D850 DSLR (f/5.3, 1/30sec, ISO 3200, FL 195mm).

Mouseover or tap on image
Mouseover or tap on image

Open: Saturday, 9 January 2021, 2145 MST
Temperature: 44°F
Session: 1585
Conditions: Clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
Filter Slider System
2" UHC filter
2" HA filter


2150 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed M42 (Great Nebula in Orion), 102X.

2155 MST: Dome OFF (onto PZT).

Mounted the D850 DSLR at prime focus using the Starizona Filter Slider System. Inserted the Explore Scientific 2" UHC Filter. Focused on the star Rigel using the Meade Bahtinov Mask and locked the mirror using the ScopeStuff LX600 12" Primary Mirror Lock.

2209 MST: StarLock ON.

I imaged the Orion Nebula, StarLock autoguided, ISO 6400, White Balance 5000K, using the filters.

UHC filter (1 minute)

HA filter (4 minutes)

The two images were merged with this result.

Click or tap on image for larger version

2229 MST: StarLock OFF.

Some breezes came up. It had been windy most of the day.

2236 MST: last look at M42, 102X.

2237 MST: LX600 OFF.

2242 MST: Dome ON.

2246 MST: did a Sky Quality reading. Reported the result to Globe at Night.

Close: Saturday, 9 January 2021, 2253 MST
Temperature: 41°F
Session Length: 1h 08m
Conditions: Clear, breezy, SQM 20.90

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