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Night Sky video,
iPhone Astrophotography Sarah's Galaxy & Whirlpool Galaxy

Posted: 3 April 2021

Wednesday, 31 March 2021, was clear but windy. Thursday, 1 April, dawned clear but even windier. As sunset approached the sky was very dusty looking. Friday, 2 April, dawned mostly clear and calm. That morning I went to Oracle State Park, our local IDA "International Dark Sky Park", to do some more video recordings for the Park's Virtual Star Party to be held on Saturday, 10 April.

Open: Friday, 2 April 2021, 1817 MST
Temperature: 91°F
Session: 1618
Conditions: Clear

12" f/8 LX600 w/StarLock
2" 24mm UWA eyepiece
2" 50mm eyepiece
1.25" 26mm eyepiece

iPhone 11 Pro Max

Set up the D850 DSLR with an 8mm fisheye lens to the north of the observatory for later sky imaging.


Took a test exposure showing the observatory and sky.


1837-1912 MST: relaxed on the observatory patio bench.

1847 MST: sunset.

1913 MST: LX600 ON, StarLock OFF, High Precision OFF.

Slewed to M52 (open star cluster) in the constellation of Cassiopeia to try to observe Nova V1405 Cas, which is near the cluster. The bright twilight sky and the low altitude would make observing the nova difficult. The nova would be behind some trees.

1922 MST: observed Nova V1405 Cas, 102X.

Switched to the 2" 50mm eyepiece for iPhone afocal imaging of two galaxies.

Slewed to NGC3628 (Sarah's Galaxy). It was not yet visible in the twilight sky.

1935 MST: M65 and M66 galaxies, part of the Leo Triplet of Galaxies, were faintly visible, 49X. 1939 MST: NGC3628, the last member of the Leo Triplet, was now barely visible, 49X.

Began preparing the D850 DSLR for sky imaging.

2003-2102 MST: took 60, in-camera intervalometer controlled, photos (f/5, 10 seconds, ISO 4000, White Balance 4550K, FL 8mm FE) every one minute.

Back inside the observatory I mounted the iPhone 11 Pro Max on the 2" 50mm eyepiece.

2012 MST: StarLock ON.

I did 10 iPhone StarLock autoguided photos of NGC3628 (Sarah's Galaxy, afocal 49X) and 10 photos of M51 (Whirlpool Galaxy, afocal 94X) using NightCap Camera (Long Exposure, Light Boost, ISO 12500, 1sec, 1 minute, 1X lens). These are how the single exposures looked (unedited).

NGC3628 (Sarah's Galaxy)

M51 (Whirlpool Galaxy)

I stacked each set of 10 images with these results.

NGC3628 (Sarah's Galaxy)

M51 (Whirlpool Galaxy)

This is the video of the night sky during one hour of my observing session (which passes in 10 seconds). Click the arrow to view the video, one each minute of time. Occasional light trails are airplanes.

2134 MST: StarLock OFF.

Viewed M51 (Whirlpool Galaxy), 102X.

2140 MST: LX600 OFF.

2151 MST: took a Sky Quality reading.

Close: Friday, 2 April 2021, 2154 MST
Temperature: 64°F
Session Length: 3h 34m
Conditions: Clear, SQM 21.08

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