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iPhone Centaurus A,
DSLR Asteroids 1989 JA & 140 Siwa

Posted: 23 May 2022

Thursday, 19 May 2022, was windy with unforecasted clouds. Missed the transit of M66 (galaxy) by Asteroid 202 Chryseis. Friday, 20 May, was clear but very windy. Saturday, 21 May, was also clear but windy. Sunday, 22 May, was cloudy and windy during the day, but conditions improved as sunset approached.

Open: Sunday, 22 May 2022, 1839 MST
Temperature: 80°F
Session: 1769
Conditions: Clear, breezy

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
1.25" 26mm eyepiece

iPhone 13 Pro Max

1849-1945 MST: Relaxed on the observatory patio bench.

1923 MST: Sunset.

1925 MST: Dome OFF.


Prepared the D850 DSLR for imaging.

1950 MST: LX600 ON, StarLock OFF, High Precision OFF.

1959-2030 MST: Relaxed on the bench and watched the stars come out.

Viewed Centaurus A (galaxy), 94X. Nice view.

Attached the LiDAR cover on the iPhone 13 Pro Max and mounted the iPhone on the 26mm eyepiece using the Levenhuk adapter.

2043 MST: StarLock ON.

iPhone afocal 94X image of Centaurus A (galaxy), StarLock autoguided, NightCap Camera (Long Exposure, Light Boost, ISO 32000, 1sec, 1 minute, 1X lens).


I am still not satisfied with my afocal images of Centaurus A. Will try again on the next session.

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

2054 MST: Wi-Fi adapter ON.

Used SkySafari 7 Pro on the iPhone to GOTO asteroid 140 Siwa. The Near Earth Object asteroid 1989 JA would also be in the same field-of-view.

2056 MST: Wi-Fi OFF.

2100 MST and 2130 MST: Imaged the asteroids, StarLock autoguided, 5 minutes, ISO 800, White Balance 4550K. There were strong breezes at times during the imaging and seeing was not good at times. Asteroid 1989 JA was close to the Earth so its image trailed during the 5 minutes exposure.

Asteroids 1989 JA and 140 Siwa

Thanks to Scott Kardel for the tip on the asteroids.

2136 MST: StarLock OFF.

2150 MST: LX600 OFF.

2155 MST: Dome ON.

2200 MST: Took a Sky Quality reading and reported the result to Globe at Night.

Close: Sunday, 22 May 2022, 2206 MST
Temperature: 67°F
Session Length: 3h 27m
Conditions: Clear, SQM 21.05

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