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Flame & Horsehead Nebulae UHC HA filters

Posted: 16 January 2021

Tuesday evening, 12 January 2021, I was a guest speaker of the Sugar Creek Astronomical Society and gave a talk on Smartphone Astrophotography to the members via Zoom.


I checked the sky after the meeting and there were some thin clouds along with some breezes. As the night wasn't very good I didn't go out the observatory. Cloudy skies continued until Friday, 15 January.

Open: Friday, 15 January 2021, 1818 MST
Temperature: 68°F
Session: 1587
Conditions: Clear

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


1822 MST: LX600 ON, StarLock OFF, High Precision OFF.

Viewed Mercury, low in the western sky, 102X.

Viewed the crescent Moon and Earthshine, 102X.

Mounted the D850 DSLR at prime focus using the Filter Slider System. Took these photos of the Moon at prime focus.

1/250sec, ISO 400

4 seconds, ISO 400

1846 MST: as the temperature was unseasonably warm for mid-January, I relaxed on the observatory patio bench while waiting for the sky to get darker and for the constellation of Orion to rise higher in the sky.

1930 MST: back in the observatory.

Focused on the star Betelgeuse with the UHC filter and locked the 12" primary mirror. Then slewed to NGC2024 (Flame Nebula).

1943 MST: StarLock ON.

Did StarLock autoguided images of NGC2024 (Flame Nebula; 5 minutes, ISO 6400) and IC434 (Horsehead Nebula; 5 minutes, ISO 12800) using UHC and HA filters. The smaller images below are the individual images through the filters and the larger images are the merged and edited result.

Flame Nebula
photo photo

Horsehead Nebula
photo photo

2031 MST: StarLock OFF.

2048 MST: viewed Mars, 102X.

2050 MST: LX600 OFF.

2056 MST: did a Sky Quality reading.

Close: Friday, 15 January 2021, 2100 MST
Temperature: 56°F
Session Length: 2h 42m
Conditions: Clear, SQM 21.05

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