I finally started gathering Hydrogen-alpha data for the Flying Bat nebula (Sh2-129) in the constellation Cepheus. What you do not see in Ha is the large, squidlike structure of oxygen that stretches from the top corner of the Bat, through those bright stars, to about the middle of the nebula For the "Squid Nebula" (OU4) I need to come back on another night to capture the OIII. The small circular reflection nebula at the top left is vdB-140. The dark nebula on the right is Barnard 152.
Notes: 67 x 300 second subs, stacked in DSS. Gear: William Optics SpaceCat51 Apo Refractor, ZWO ASI1600MM-Pro mono camera, Antlia Pro 3nm Ha filter, Sky-Watcher EQ6R Pro equatorial mount.
M33, the Triangulum Galaxy in Ha+RGBColor with the SpaceCat51 and ZWO ASI071MC cooled color camera + Atik 414EX monochrome camera. I processed some 2018 and 2019 data to see what kind of detail I can get out NGC 604--that's the large pink mass at the middle bottom of the galaxy in this rotation. NGC 604 is a vast HII region, much brighter and 40 times larger than the Orion Nebula in our galaxy. M33 is a little under 3 million lightyears away.
Andromeda (M31) was the first deep sky object I captured with a camera--an old Nikon D40x DSLR. The Orion Nebula (M42) was the second. For many years M31 was my favorite galaxy and it is in many ways the ideal galaxy; it's a massive spiral at the perfect photographic angle from our perspective, here in the middle of our own galaxy. At two and a half million lightyears, it's not far away. And while M101, the Pinwheel Galaxy, is perfect from a galactic structure point of view, being a face-on from our perspective (or top down), Andromeda is cinematically posed for all of us taking pictures from earth. Galaxies are not really my thing. I usually focus on narrowband imaging of nebulae, supernova remnants, and other large structures within the Milky Way--so, thousands of lightyears away, not millions. I almost always shoot with sub-1000mm focal lengths, and galaxy imagers are usually running with 2000mm or more. OTAs of 3000mm and up are common.
Andromeda is certainly one of my favorites, but I think the Triangulum Galaxy (Messier 33, M33, NGC 598) in the constellation Triangulum is my favorite northern hemisphere galaxy. It's kind of chunky with vast HII regions (the pink structures scattered along the spiral arms). It gets a little thin out toward the edges; not the smooth plane of stars you see in the Andromeda galaxy. It's made up of 40 billion stars rather than the trillion or so in Andromeda. M33 is another galactic neighbor and close enough to capture with medium focal lengths.
I was experimenting with UV/IR cut filters on the ZWO ASI071MC last night, and took a bunch of test subs without guiding--all 30 second exposures. This is 97 sub-exposures of M13 (NGC 6205) in the constellation Hercules. Messier 13, like most (all?) globular clusters orbit in the halo of the Milky Way galaxy, a good distance away from the core, both above and below the galactic plane.
And more stars (IC 4756 star cluster). More testing with the IR/UV cut filter and the ZWO ASI071MC camera.
North America Nebula (NGC 7000, left) and Pelican Nebula (IC 5070, top right) in the constellation Cygnus. Narrowband in the SHO palette. 68 x 240 second subs in Ha, OIII, SII. I kept the Hydrogen (green) levels pretty even.
A wide-field narrowband (hydrogen-alpha) image of the Pacman Nebula in Cassiopeia. This emission nebula is a little under 10,000 lightyears away in the Perseus Spiral Arm of our galaxy, and it doesn't seem quite large enough for this view--except to show that Pacman is alone out there in this region of space (from our perspective). And that's one of the many cool aspects that makes NGC 281 fascinating to capture--there are so many others, an intense star-forming region, it's a great Hubble palette target, large examples of bok globules, X-ray imaging reveals a dense molecular clouds of hydrogen and carbon, feeding the process of star-creation, to name a few.
The double star eta Cassiopeiae (η Cassiopeiae) is the bright point of light above Pacman/IC 11 (brightest in the frame). Eta Cass. is made up of eta Cassiopeiae A, a sun-like G-type main-sequence star, and its smaller K-type orbiting companion, eta Cassiopeiae B. With a little research, this might be a cool SF world to tell a story around--the main star is like ours, but with an additional sun orbiting. And it's only 19.5 lightyears away.
Imaging notes: 57 x 300-second subs in 3 nanometer hydrogen-alpha. No calibration frames. Guiding was better than expected, with total RMS hovering between .7 and .9 arcseconds. Seeing was below average--astronomical seeing, which is impacted by turbulence and temperature differences in the atmosphere. It's pretty common to have a clear night with terrible seeing. There's a time and place for twinkling stars--like writing a song, but they're the bane of astrophotographers. Gear notes: ZWO ASI1600MM-Pro monochrome camera, Antlia 3nm Ha Pro narrowband filter, William Optics SpaceCat 51 apochromatic refractor, Sky-Watcher EQ6-R Pro mount.
Another one from last night's imaging run--finished up last night, with 34 subs from November 1st: Our largest galactic neighbor, Andromeda, with the William Optics SpaceCat 51 refractor and the ZWO ASI071MC cooled color camera.
From last night's imaging run: The Orion Nebula (M42) is one of my all-time favorite deep sky objects, and the Constellation Orion is in my top five places to go with a telescope. Imaging Notes: Ha+RGB, Ha: 55 x 240-second subs, color: 123 x 120-second subs stacked in DSS, processed in PSCC2022. William Optics SpaceCat51 Apo refractor, ZWO ASI071MC cooled color camera & ASI1600MM-Pro monochrome camera, Controller: INDI, Ekos, KStars.
This is the blue bandpass of the Andromeda Galaxy (M31), revealing dense spirals of dust that wind through starfields and curl around the galactic core. I have labeled NGC 206, one of the brightest of the star clouds inside Andromeda, along with a couple of M31's captive galaxies (M32 and M101). Imaging Notes: 51 x 120-second stacked subs from my WilliamOptics SpaceCat51 (250mm FL) and ZWO ASi1600MM-Pro mono camera.