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SESSION 26 · 11/26 · WORKED

The phone, on a moonless morning

After Saturn, the phone. A few frames at eleven, nothing worth keeping but one wide field. Then out again before four with the Moon new and down, and the southern sky high: the Large Magellanic Cloud, the Milky Way through Carina, Orion in the north. Every keeper was ten seconds or close to it on the phone's ordinary lenses. Every zoomed frame was a reject.

Brendan, Goolwa SA · 11/26

Targets
Large Magellanic Cloud, Canopus, Carina Nebula, Orion, Sirius, Aldebaran, M42
Gear
iPhone 17 Pro Max
Outcome
Worked
Chapter
The new camera
A dark blue sky full of stars above the dark edge of a roof. In the middle a small pale smudge with a ragged edge, the Large Magellanic Cloud; up and to its left a single bright blue-white star, Canopus. A wisp of cloud upper left
The Large Magellanic Cloud, 03:53, ten seconds at ISO 1600 on the phone's main lens. Canopus is the bright star above it. The cleanest of the four frames that have it.

iPhone 17 Pro Max, from the back yard. Two goes: 23:01 to 23:11 on 8 November, after the Saturn runs in Saturn through poor air, and 03:44 to 03:56 on the 9th. New Moon, set at 19:01, so a dark sky both times. Written up on 9 November.

23:01 to 23:11, the wrong lenses

Seven frames. The southern sky was still low: Orion just up in the east, Carina under ten degrees.

frame time lens exposure ISO verdict
IMG_2294 23:01 0.5x, 14 mm 1 s 5000 reject, nearly black
IMG_2295 23:03 0.5x, 14 mm 10 s 3200 keep, wide star field
IMG_2298 23:06 2x, 48 mm 10 s 4000 reject, stars trailed
IMG_2299 to 2302 23:08 to 23:11 4x and 8x, 100 to 200 mm 0.5 s 8000 reject, a few stars

The telephoto would not give more than half a second. At ISO 8000 that is a handful of points and nothing to say which.

03:44 to 03:56, the southern sky overhead

Thirteen frames and a short video. Canopus 72 degrees up, nearly overhead; the Large Magellanic Cloud 56 degrees up due south; the Carina Nebula 38 degrees in the south-east; Orion and Sirius high in the north.

frame time lens exposure ISO target verdict
IMG_2304 03:44 video 4.5 s one faint point reject
IMG_2305 03:46 1x cropped, 198 mm 2 s 6400 M42 reject, trailed and noisy
IMG_2306 03:47 1x cropped, 198 mm 10 s 3200 reject, noise
IMG_2307 03:48 1x cropped, 198 mm 10 s 1000 reject, noise
IMG_2308 03:49 1x, 24 mm 0.25 s 2000 reject, underexposed
IMG_2309 03:49 1x, 24 mm 10 s 2500 LMC, Carina Milky Way, Canopus keep, a satellite
IMG_2310 03:51 1x, 24 mm 10 s 6400 LMC, Carina Milky Way keep, cloud coming in
IMG_2311 03:52 1x, 24 mm 10 s 3200 LMC, Canopus keep, high cloud
IMG_2312 03:53 1x, 24 mm 10 s 1600 LMC, Canopus keep, the cleanest
IMG_2313 03:54 1x, 28 mm 10 s 1600 Carina and Vela Milky Way keep
IMG_2314 03:55 1x, 28 mm 2 s 6400 Carina Nebula, Canopus keep
IMG_2315 03:56 1x, 28 mm 10 s 1250 Orion, Sirius, Aldebaran, Hyades keep, best framing
IMG_2316 03:56 1x, 24 mm 2 s 1600 Orion reject, underexposed

Identified by eye and checked against where each one was at 03:50 from here, not plate-solved. Confident on the Cloud, Canopus, the Carina band, Orion, Sirius and Aldebaran; less so on fainter single stars.

By lens

lens frames keepers
0.5x, 14 mm 2 1
1x, 24 to 28 mm 9 7
anything zoomed, 48 to 200 mm 8 0

What worked on the Cloud: ten seconds, main lens, ISO 1600 to 3200. Ten seconds was the longest the phone gave all night. The ISO 6400 frame is the noisiest of the four.

Zoom gave nothing. empty magnification, on a phone: the 2x and 8x settings on the main lens are crops of it, the telephoto is a smaller, slower lens held to half a second. M42 is really in IMG_2305, a blue patch where it should be, but under smeared stars and noise. The written lesson is the phone wide lens did all the work.

Left for next time

A starry sky over the corner of a roof. Orion's belt and sword in the middle, a bright star upper right, an orange star with a loose cluster lower left
Orion, 03:56, ten seconds at ISO 1250. Sirius is the bright star upper right, Aldebaran and the Hyades lower left.
A dark sky with a faint band of the Milky Way running down from the middle to the lower edge, with a brighter knot in it, and a bright star upper right
The Milky Way through Carina, 03:55, two seconds at ISO 6400. The brighter knot low in the band is the Carina Nebula; Canopus upper right.
A wider starry sky over a corrugated roof, the Milky Way down the left side, a pale smudge to the right of centre, clouds across the top and a straight line of a satellite upper right
Both in one frame, 03:49, ten seconds at ISO 2500: the Carina Milky Way on the left, the Large Magellanic Cloud right of centre, Canopus between them at the top, and a satellite.
A dark brownish field of smeared, doubled star points with a small blue-violet patch near the top
M42, 03:46, two seconds at ISO 6400 on the main lens cropped to 198 mm. The nebula is really there, the blue patch, but every star is a smear and the rest is noise. Eight zoomed frames, no keepers.