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Deep Sky Dan

Astronomy, astrophotography, and telescopes! (brand collaborations are welcome)

I take photos of planets and deep space objects using my smartphone camera & dedicated astro cameras using various size telescopes.

29/05/2026

The Needle Galaxy

This bright galaxy is one of the most famous examples of an edge-on spiral galaxy, oriented perpendicularly to our line of sight so that we see right into it's luminous disc. NGC 4565 has been nicknamed the Needle Galaxy because, when seen in full, it appears as a very narrow streak of light on the sky. It's located 30 to 50 million light-years away in the constellation Coma Berenices, it spans roughly 100,000 to 140,000 light-years across and is considered a near-twin to our own Milky Way.

•Central Bar: Infrared observations reveal that its bright central core actually has a boxy, elongated bar structure, much like astronomers believe exists at the center of the Milky Way.

•Dark Dust Lane: A prominent, thick band of cosmic dust cuts cleanly through the bright yellowish starlight of the galactic disk.

Usually I'd be shooting galaxies like this with my 8" SCT, but ever since I got my hands on this 92GX from Nakoh Optics here in Japan I've had a blast imaging with it. And this beautiful galaxy was first light. The last time I photographed the Needle galaxy was with my smartphone so it's nice to finally give it some proper attention and reveal those beautiful dust lanes. Watching exposures popup on screen in bortle 3 skies sure is amazing. A small feature I really like are all the tiny background galaxies. Thus far the 92GX has been a great scope. It will be released for sale in the coming months.

• Nagano, Japan
• Bortle 3/4/5 locations
• Nakoh Optics 92GX Quintuplet Refractor
• Sky-Watcher EQ6-R Pro (tuned)
• Player One Poseidon-C Pro
• Player One 2" Anti-Halo UV/IR cut
120 x 300s, -20°, 0 gain, 25 offset
15 darks, 15 flats, 15 dark flats (per session)
• Gemini Astro EAF
• SVbony SV241 Power Hub
• SVbony SV165 30mm mini guide scope
• SVbony dew heater strips
• Player One Sedna-m guide camera
• Software: NINA, PHD2, Win10 laptop
• Stacking: Astro Pixel Processor
• Processing: Adobe Photoshop 2026

22/05/2026

Milky Way from my smartphone!

I stacked 20 x 10sec of the recent image I posted, then processed the stack to get to this. Yes, I went nuts to try and get alot more out of this super short stack than what should be possible😅But you can clearly define alot of regions of interest.

21/05/2026

Milky Way from 1700 meters up in a bortle 3 area😍

10 second raw exposure taken with my Samsung Galaxy S10+ using the DeepSkyCamera Pro app.

15/05/2026

Hercules Globular Cluster
Messier 13

M13 is located in the Hercules constellation. It's one of the brightest and best known globular clusters in the northern sky. The cluster has an apparent magnitude of 5.8 and lies at a distance of 22,200 light years from Earth. It's designation in the New General Catalogue is NGC 6205.

M13 has an estimated age of 11.65 billion years and contains about 300,000 stars. The estimated mass of the cluster is about half a million solar masses.

M13 stretches across 20 arc minutes of the sky, which corresponds to a linear diameter of 145 light years. The cluster can be seen without binoculars in exceptionally good viewing conditions, with clear skies and no light pollution.

The brightest star in M13 is V11, a red giant classified as a Cepheid variable. V11 has a visual magnitude of 11.95 and lies approximately 25,100 light years from Earth.

M13 contains an unusually young, B2-type star, designated Barnard 29. The star does not really belong to the cluster, but was presumably picked up by M13 on its orbit around the Milky Way. Other stars in the cluster are very old and only have about 5 percent of the Sun’s iron content as they were formed before the stars in our galaxy created metals. M13 also contains about 15 blue stragglers, old stars that appear younger and bluer than their neighbors.

I took this photo from my backyard here in Nagano City, Japan. Each exposure is only 30 seconds, and a total time of 15 minutes.

• Nagano City, Japan
• Bortle 5
• Nakoh Optics 92GX Quintuplet
Refractor
• Sky-Watcher EQ6-R Pro (tuned)
• Player One Poseidon-C Pro
• Player One 2" Anti-Halo UV/IR cut
• Gemini Astro EAF
• SVbony SV241 Power Hub
• SVbony SV165 30mm mini guide scope
• SVbony dew heater strips
• Player One Sedna-m guide camera
• Software: NINA, PHD2, Win10 laptop
• Stacking: Astro Pixel Processor
• Processing: Adobe Photoshop 2026

#星 #銀河

04/05/2026

A closer look at Arp 85...
(Messier 51 & NGC 5195)

These two interacting galaxies are in Canes Venatici. An extensive "bridge" connects the 60 thousand light year wide M51 with it's smaller companion, NGC 5195. Clusters of hot bright young stars and gases heated by their radiation illuminate the spiral arms and clearly define them. Thick dust lanes straddle the arms, sweep across the "bridge" and partially obscure the companion. The pair is just over 30 million light years away.

When I photographed this popular spring target a few years ago I was very new to using NINA and a cooled camera. So many settings to figure out. I didn't get guiding right because I couldn't find a guidestar using a ZWO 290mm mini & OAG. And at that time I was doing manual focusing with a bahtinov mask so stars are not as tightcas they could be. Later, I found a light leak because of one spacer not being fully tightened. Alot of challenges to overcome but I was able to eek out 8 hours of data. I recently reprocessed all this data to get to this finished image.

30/04/2026

The Svbony SV555 has been a fantastic telescope for the price. I've done some amazing work with it and the Player One Astronomy Poseidon-C Pro.

https://www.facebook.com/share/v/16uHoHGrzZ/

27/04/2026

Caught it!

You are looking at a newly discovered "reddened Type II supernova" in galaxy NGC 5907. Also known as the Knife Edge galaxy, it sits about 50 million light years away in the constellation Draco. On April 22nd 2026, Japanese astronomer Yasuo Sano made the discovery and since then this supernova has been captured by numerous amateur astronomers. I was lucky and finally got my chance to capture it before some clouds rolled in last weekend. This is a singe 5 minute exposure that has been slightly processed in order to see it better.

If you have a telescope and camera see if you can catch it too!

21/04/2026

Hubble turns 36 years old this week! NASA is kicking things off with a new view of the cosmos, courtesy of the telescope-of-honor!

The colors in this image from the NASA/ESA Hubble Space Telescope tell a story about density in the Trifid Nebula, a star-forming region about 5000 light-years from Earth. The top left, where it is bright blue, has the smallest amount of dust. Here, powerful ultraviolet light stripped electrons from nearby gas, creating a glow, with winds creating a bubble by clearing out surrounding dust.

An example of active cloud destruction is toward the top of the head-shaped area with two “horns.” Bright yellow gas streams upward where gas and dust are being destroyed.

Thicker dust appears dark brown, like mud. In the far-right corner, which is nearly pitch black, the dust is the densest.

Fully formed stars — bright orange orbs — are scattered across the scene. Their light and stellar winds have also cleared the immediate areas around them.

Over millions of years, the gas and dust that make up this nebula (also known as Messier 20 or M20) will disappear and only stars will remain.

Credit:
NASA, ESA, STScI, N. Bartmann (ESA/Hubble)
Music: Stellardrone - Ascent

$I recently posted that I have been testing the 60GT triplet APO refractor from Nakoh Optics. I have some results and a f...$

18/04/2026

I recently posted that I have been testing the 60GT triplet APO refractor from Nakoh Optics. I have some results and a few thoughts I'd like to share.

When I received this telescope and unboxed it my first thought was "wow this is a nice looking scope". It does look similar to another famous Japanese brand. After going over it I can tell you it's a well-built solid design. It comes already assembled so you don't have to put anything together, but it can be customized. Right out of the box you can put in a diagonal and eyepiece and start viewing. If you plan on doing any type of astrophotography then you'll need either the 1.0x flattener which will keep you at the native 360mm f/6, or you can get .65x reducer and make this telescope a super fast 234mm f/3.9 widefield option for those bigger targets. The focusing mechanism is buttery smooth and the EAF attached easily. I like to have the ability to rotate my camera up 360° if needed. Unfortunately the dew shield is not adjustable but no big deal. I think the only upgrade I would do is a bigger CGE dovetail bar.

The big question...what's the image quality? Well, my testing was done with the 1.0x flattener. You can see my exact setup in the posted photos. I live in a Bortle area with 6/5/4 zones. Yes, I have all 3 gradients in my sky. It's crazy. Single autostretched 180 second exposures show perfectly round, and slightly fuzzy, stars from edge to edge. No issues here. I photographed the Beehive Cluster for one hour and the Pinwheel Galaxy for 3 hours. Full calibration frames were used. After some processing in Photoshop I could see very little if any chromatic aberration in the stars. The natural blues and oranges are retained very well. I'd say this triplet is well corrected with it's ED glass and SD glass combo.

Final thoughts..

This telescope was a pleasure to use. Every piece on it is high quality. No negatives that I can report besides wanting to change the dovetail. I'm very happy with my image results even for such short integration time. I'd love to see what it can do at f/3.9 at my dark sky location. If I get a chance I will update this post. If you are looking for a triplet with these characteristics then you won't be disappointed with this telescope.

Please go to their website for more information: www.nakoh.co.jp
(Japanese or English is available)

(all thoughts and opinions are that of my own and in no way have I been told what to say by anyone)

住所

Nagano-shi, Nagano