Entries tagged as star

Sombrero Galaxy

Sombrero Galaxy seen on the night between April 18 and 19, 2018 (25% size)

I was looking to photograph a galaxy that was shaped distinct enough to look like something other than a blob of fuzzy light ball under limited equipment and conditions. Looking through the available targets, I picked out the Sombrero Galaxy, also known as Messier 104. This is a spiral galaxy in the Virgo constellation that resembles the shape of a sombrero, a Mexican style wide-brimmed straw hat.

As you can see here, the observation and the photography were successful. The "brim" definitely makes the galaxy easily identifiable, helped by the use of a filter to cut down the ambient light pollution. The photo isn't quite as smooth as I liked due to the field rotation inherent in the Alt-Az mount. This prevented me from using an exposure time longer than a minute, and I had to compensate with a high ISO setting.

Telescope: Celestron NexStar 6SE
Device: Sony A5000 (prime focus)
Settings: (1500mm) - ISO 3200 - 60s - (f/10)
Filters: Baader Moon & Skyglow
Time: 2018-04-18 23:08 ~ 2018-04-19 00:48 KST
Location: Naju, Korea
7 photos stacked with DeepSkyStacker 3.3.4

Nebulas and galaxies in the spring sky

Orion Nebula (Messier 42, 25% size)

I haven't taken a look at nebulas and galaxies in several years - the last time I did so was back in November 2015. With the clear evening skies persisting for a few days, I thought that it was a good time to make a return observation. The easiest, and thus the first target was the bright Orion Nebula. I first made several attempts with my iPhone X, but it did not yield the level of quality I wanted and switched to Sony A5000 for the result above. As it was April, the nebula was heading towards the horizon in the southwestern sky and thus subject to less than dark background and drowning out darker portions.

Bode’s Galaxy (Messier 81, 38% size)

Moving to the northern sky, I took a look at something I haven't checked out since moving to Naju - the Bode's Galaxy and the Cigar Galaxy. I last saw them in May 2014 in Suwon. Due to the worsening light pollution I can't say I had better observation conditions, but I did have better equipment now. And the results speak of this advantage, as the galaxies were captured in finer detail. I especially like how the variation of brightness appears in the Cigar Galaxy below.

Cigar Galaxy (Messier 82, 38% size)


Telescope: Celestron NexStar 6SE + f/6.3 focal reducer
Device: Sony A5000 (prime focus)
Settings: (945mm) - ISO 1000(#1) / 2500(#2) / 3200(#3) - 30s - (f/6.3)
Filters: None
Time: 2018-04-09 20:23-20:38(#1) / 22:27-22:40(#2) / 22:49-23:10(#3) KST
Location: Naju, Korea
5(#1) / 10(#2) / 13(#3) photos stacked with Deep Sky Stacker 3.3.4

The streak of Iridium 60's flare

Iridium 60 in the northern sky on August 30, 2016 (14% size)

It's been more than two years since I talked about satellite flares here, but I now have something to show you. As you can see, I had a camera successfully capture the flares coming from an Iridium satellite for the first time. Past efforts used iPhones because I was focused in capturing the motion of the flares. In this photo, the ever-growing Naju Bitgaram City provided a colourful backdrop.

Device: Sony A5000 + SELP1650 (E PZ 16–50 mm F3.5–5.6 OSS)
Settings: 24mm - ISO 400 - 20s - f/4.5
Filters: None
Time: 2016-08-30 05:06 KST
Location: Naju, Korea
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Getting a less noisy shot of the Milky Way

Milky Way over the apartments on September 29, 2016 (14% size)

Nearly two months ago, I realized that the southern window at home provides a view of the Milky Way with long-exposure photography. Although the result from that time was satisfactory, I felt that a stacked approach would be even better. And now, you see the result of stacking eight photos. It's indeed much smoother even at a larger size.

By not using a star tracker, though, the stars were subject to lens distortion at the edges. This is where the flaws of the bundled lens of the A5000 become quite apparent. But I decided to leave it like this since it draws your attention to the center.

Device: Sony A5000 + SELP1650 (E PZ 16–50 mm F3.5–5.6 OSS)
Settings: 16mm - ISO 1000 - 20s - f/3.5
Filters: None
Time: 2016-08-29 21:48-22:05 KST
Location: Naju, Korea
8 photos stacked using Pixelmator
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Perseids meteor shower 2016 in Naju

Perseids meteor streaks across the top right over the ancient tombs in Naju (14% size)

This year's Perseids meteor shower was predicted to be prominent, garnering lots of public interest. Unfortunately for someone in Naju, the northern sky that the shower was to take place is polluted with light from Gwangju, making it hard to watch the fainter ones. To get a better view, I moved about 17km southwest to the Naju Bannam tumuli (ancient tomb mounds that encompass Sinchon-ri, Deoksan-ri, and Daean-ri tombs) next to the Naju National Museum. Upon arrival, I was disappointed to discover that the light pollution was still quite bad.

It was still better than being at home, so I set up my camera with the Deoksan-ri tombs #2 (left) and #3 (right) in front. There were already two families nearby who came to watch the sky. In the two hours I stayed, I was able to watch about five meteors falling, far less than the supposed maximum of 150 per hour. Of those, the camera caught two of them, the most striking one being shown here. The streak was going through the Andromeda constellation; the fuzzy dot to the left of the streak is the Andromeda Galaxy.

Meanwhile, the airplanes appeared much more often in the sky - there was one every five minutes or so. This is due to being more or less in the direct path of the flights between Seoul and Jeju, as well as Incheon and Southeast Asian cities. Even in this photo, the Mandarin Airlines flight AE231 (Incheon-Taipei) was caught on the left as a knotted line.

Device: Sony A5000 + SELP1650 (E PZ 16–50 mm F3.5–5.6 OSS)
Settings: 16mm - ISO 400 - 15s - f/3.5
Filters: None
Time: 2016-08-12 23:37:27 KST
Location: Naju, Korea

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