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.
My William Optics GT81 Apochromatic triplet refractor, the day it arrived (left) and today (right)--that's an FPL-53 front element, 81mm aperture, 478mm focal length, 382mm at f/4.7 with the field flattener. I've been capturing the beautiful night sky with this awesome piece of hardware for nearly seven years. I bought it August 2015 and here we are in May 2022. I have captured hundreds of nebulae, galaxies, supernova remnants, and various phases of our moon. Over the last seven years I've captured the distant light of stars and emission nebulae in thousands of one, two, five, and ten-minute sub-exposures. Here's to seven more. Thank you, William Optics!
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.
The evening weather hasn't been super clear lately, but it has given me a chance to test out the all-sky camera. This takes a pic every 20 seconds through the night and creates a time lapse video, a stacked star-trails image, and a keogram (a keogram is single image visualization that represents an entire night's atmospheric activity). And of course, there's a "Live View" so I can always check on the sky's current conditions.
I'm running Thomas Jacquin's awesome open-source AllSky software for Raspberry Pi:
Today starts my first full test of the setup, with daylight solar charging and continuous operation. Here's the current system, with the dome taped down for now, ZWO ASI120MC color astro camera, 6mm super wide-angle lens, Raspberry Pi 3b, lithium battery, and 10 amp PWM solar controller. I drilled two holes for ventilation, mainly to test the need for separate dew control. My hope is that there's enough heat rising from the Raspberry Pi CPU fans to get warm air circulating under the dome--with enough of a temp boost to prevent condensation from forming.
Examples of the camera's field of view from the back deck, close to the house. I have it in the middle of the backyard now, with a full view of the sky.
A snapshot from the April 3rd night sky:
About 450 lightyears away, the Pleiades, Messier 45 is one of the most recognizable open star clusters in northern hemisphere skies. Imaging Notes: 28 x 480 + 28 x 600 second subs, William Optics SpaceCat 51 APO Refractor, ZWO ASI071MC camera, iOptron CEM25P mount.
Astro setup for this imaging run:
With the stars removed you can really see the hydrogen cloud structures. It is the intense radiation from those stars that drives the currents and eddies and walls of cloud. And then there's the "finger of Orion", middle left, pointing at NGC 1976, and clearly saying, "that's my favorite nebula in the whole galaxy".
Narrowband (3 nanometer hydrogen-alpha) crop of the central region of the California Nebula (NGC 1499) in the Constellation Perseus. I used the neural-net based StarNet to remove the stars from the final image. So we're only seeing the trillions of miles of hydrogen, along with dark bands of dust and interstellar debris.