Astro Session - January 13, 2018
It's winter and that's when Orion is arguably the main attraction in northern hemisphere skies. HaRGB of the Horsehead Nebula (Barnard 33) along with the reflection nebula NGC 2023 (below and left), part of a whole neighborhood of nebulosity around the leftmost star in Orion's Belt, the blue supergiant Alnitak. (I kept Alnitak out of frame, but it would off to the left with a wider field of view). The Horsehead is an absorption (or dark) nebula about 1500 lightyears from Earth, and shows up so prominently because it's blocking most of the starlight behind it. (10 x 600 second Ha frames, 10 x 240 second RGB frames, 24 dark cal frames taken with an Atik414Ex mono CCD, William Optics GT-81 + 0.8x Field Flattener/Reducer f/4.7, iOptron CEM25P EQ mount, Astronomik 12nm Ha filter, Baader RGB filters, WO 50mm guide scope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control. Location: Stratham, New Hampshire, US. ~Bortle 4)
The full FOV for this shot:
Posted January 13, 2018
Astro Session - January 10, 2018
The temps are nice--downright warm compared to what we've been hit with over the last couple weeks. The clouds are the problem. They gave me two hours of clear skies, and I spent them taking a batch of five minute exposures of M42, the Orion Nebula. (Atik414Ex mono CCD, William Optics GT-81 + 0.8x Field Flattener/Reducer f/4.7, iOptron CEM25P EQ mount, Astronomik 12nm Ha filter, WO 50mm guidescope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control).
Posted January 10, 2018
Astro Session - December 27, 2017
California Nebula NGC 1499, an emission nebula in the constellation Perseus. Named after the Golden State because of the similarity in shape--and this is just the lower portion, basically Santa Barbara on down, although depending on how you match up coastline similarities you might be able to squeeze in everything up to Pismo Beach. I attempted to do some Ha + RGB color process stuff with this set, and I think it worked out. I overloaded the red channel to bring out some contrasting shades, and the GB didn't contribute much. NGC 1499 is mostly ionized hydrogen, and it's massive, almost 2.5°. I'd have to take two or three combined shots to get the whole nebula in one image with the camera+telescope FOV of my setup: Atik414Ex mono CCD, William Optics GT-81 + 0.8x Field Flattener/Reducer f/4.7, CEM25P EQ mount, Baader and Astronomik filters, WO 50mm guidescope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control.
Posted December 27, 2017
Astro Session - December 26, 2017
I took several hours of hydrogen-alpha, oxygen 3, sulfur 2, and RGB images last night. Here's the color version of the Rosette Nebula (nebular region) with OIII and SII frames added to a bunch of Ha frames I shot at the beginning of the month.
Okay, this new astro setup worked well (see yesterday's post). I just bolted on the mount, did a quick polar alignment, and I was taking beautiful twenty-minute exposures of NGC 1499 (California Nebula). I shot some hydrogen-alpha of the California while waiting for the Rosette Nebular region to come into view.
I have been on this automated portable astrophotography path for a while; it's been a slow but continuous process of remote controlling my entire astro imaging rig from anywhere. I set it up, and as long as there's power and wifi, I'm good to go. This latest iteration, making the whole rig portable, is going to make things easier on those nights when I know I'll only have two hours of clear skies. Before now I wouldn't even think about setting up because that could eat up an hour alone. (Atik414Ex mono CCD, William Optics GT-81, CEM25P EQ mount, WO 50mm guidescope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control)
Four stacked 1200-second frames of NGC 1499 with the 12nm Astronomik Ha filter:
Posted December 26, 2017
Astro Session - December 26, 2017
A couple test Ha frames of Lower's Nebula (SH 2-261) in the constellation Orion. I only took two exposures of Lower's Nebula while waiting for the Rosette Nebula to rise, and it reminded me of a scene in the movie Roxanne with Steve Martin (CD Bales) and Daryl Hannah (Roxanne):
C.D. Bales: You must know about M31.
Roxanne: Yeah.
C.D. Bales: Now, see, I like it when they give astronomical objects names, you know, like "Andromeda" and "Saturn" and "Sea of Tranquility." This whole numbering thing is just too boring for us civilians.
Roxanne: Do you know how many objects are up there?
C.D. Bales: Well, I know it's over fifty.
That's the problem when you're a constellation like Orion, with a nebula so massive and bright you can see it clearly without a telescope (M42), or you possess dark nebular structures famously shaped like animals (Horsehead nebula, Barnard 33). You get overlooked if you're not a superstar or supernova remnant or "The Great" Orion Nebula. Yeah, that's Lower's Nebula (SH 2-261), which I'm sorry to say, I had never heard of before last night. Unfortunately that's probably because Lower's Nebula isn't the buckle on Orion's Belt. It isn't even hanging off of Orion's famous belt. It is literally out on a distant arm of the constellation--yes, Orion has one arm raised, far away from the Belt, and the famous stars like Betelgeuse, Bellatrix, and Rigel, and that's where you'll find this obscure cloud of hydrogen that doesn't even have a wikipedia page (In English. I found an Italian page for SH2-261. Nicely done, Italy.)
(Subframe info: one 600-second exposure and one 1200-second exposure stacked in DSS, no calibration frames, Atik414Ex mono CCD running at -10C, Astronomik 12nm Ha filter, William Optics GT-81, CEM25P EQ mount, WO 50mm guidescope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control)
Posted December 26, 2017
Astro gear - December 25, 2017
My Winter Astro Setup, essentially the same William Optics GT-81 - iOptron CEM25 combo, with the addition of the iOptron Tri-Pier Adapter, some 6x8 aluminum plates off eBay, and one treated 4x4 post from Home Depot.
The good side of winter and astrophotography is it’s usually dry on clear nights--and “clear” really means clear in terms of astronomical seeing, atmospheric turbulence and all that. Downside is that it’s freakin’ cold. Tonight it’s supposed to get down to about -8°C (about 20°F), pretty cold to be out for a long time, but not painfully cold.
Here are a couple shots of my setup for tonight--and possibly the rest of the winter. (William Optics GT-81, CEM25P EQ mount, Atik414Ex mono CCD, WO 50mm guidescope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control). What’s cool is that I can unbolt the mount with the pier adapter and aluminum base plate (they’re all bolted together) from the 4x4 post and top plate, and carry in the entire setup--mount, scope, cameras, etc. What I especially like about this is the ease with which I can setup and tear down each night. The whole thing remains balanced and ready to go, with polar alignment reduced to very fine adjustment to zero in on the NCP.
Note on my other mount: I probably won’t use my Orion Atlas EQ-G mount until spring when things start to warm up, and that’s based on the weight of the Atlas and the low temperatures--with ice adding some difficulty to the setup process. (Yeah, I don’t want to lug around this monster with any probability of slipping, landing on my back, and having to catch fifty or sixty pounds of metal out of the air before it kills someone). The average winter low in New Hampshire is around -12°C, and the average winter high temp is still below 0°C (around 30°F). It’s not unusual for things to get down to -20 to -30°C (-10 to -20°F). We’re still in December, so early in the season, but we’re already getting repeated snow storms interspersed with temps above 0°C (32°F). We typically get a few days of warmer weather here and there, snow and ice melting weather, but there haven’t been enough of them to make a dent in the accumulating snow and ice we have in the yard, driveway, or back deck. We just ended yesterday (the 25th) with another 6 inches or so. When there’s ice, lighter is better.
Posted December 25, 2017
Astro Session - December 1, 2017
We were very close to a full moon last night, so my astro imaging options were limited to narrowband. I spent most of the night with Hydrogen-alpha, an inexpensive 12nm Astronomik filter, but as you can see, able to bring out some fantastic contrast, depth, and details throughout this region of interstellar ionized hydrogen. (This is the filter I currently have in the 1.25" wheel. My Baader 6nm Ha is in the 2" filter wheel)
The "Rosette Nebula" is a cluster of nebulosity that includes NGC 2237, NGC 2238, NGC 2244, NGC 2239, NGC 2246 and more. The Rosette is a bright mag 9 area of the sky about 1.3° across in the constellation Monoceros. (subframe info: 28 600 second exposures in hydrogen-alpha, no calibration frames, Atik414Ex mono CCD running at -10C, Astronomik 12nm Ha filter, William Optics GT-81, CEM25P EQ mount, WO 50mm guidescope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control). https://www.astrobin.com/324406/
One of many reasons I love the Atik 414EX is how clean (free of noise) the light frames are when you cool the sensor down to -10C or below. I didn't shoot dark frames, or any other calibration frames last night, and didn't use any from my library when stacking.
My last target of the night: center portion of IC 2177, the "Seagull Nebula" in the constellation Monoceros. There's noise that showed up during stretching, but this one of IC 2177 is just 4 stacked Ha frames, each 600 seconds.
Here's a screenshot of Ekos and KStars, in the process of capturing 600 seconds of photons landing in my backyard from the Rosette Nebula. This is pretty much what I see--the tools I work with--when remotely controlling the mount, telescope, cameras, targeting, focusing, plate solving, and more. And that's what a single 600-second frame looks like. With stacking I'm obviously getting a lot more signal to noise.
Posted December 1, 2017
Astro Session - November 10, 2017
Constellation Orion (and that's Sirius in the lower left). I was out in the cold last night, with the Nikon D750 (24mm, 30 sec. exposure, ISO 800). Love that Hampton sky glow.
