Astro Session - October 4, 2017
Astrophotography with a full moon! I switched to narrowband imaging a few days ago, which has the advantage of limiting the light to a very narrow range, and not really being affected by the light of the sun reflected off the big smiling face of our moon. The requirements are far stricter than color or LRGB imaging in terms of exposure times (10 - 30 minute exposures are typical), which in turn require far tighter alignment for the mount and guiding system. I have three narrowband filters--Ha (hydrogen alpha) OIII (oxygen) and SII (sulfur), all with 6nm bandpass. For these images below I'm only imaging with the Ha filter and the Atik 414EX monochrome CCD camera. Image info: top-left: IC 1848 Soul Nebula (the center portion), bottom-left: IC 1369a Elephant Trunk Nebula, right: NGC 281 Pacman Nebula. 4 x 20 minute (1200 second) subs stacked in DSS.
Posted October 4, 2017
Astro Session - October 2, 2017
I love this early autumn weather! Here's a 20 minute hydrogen alpha exposure/sub of IC 1805, the Heart Nebula, a diffuse nebula in Cassiopeia. FoV: 1.05 × 0.79° (William Optics GT-81, Atik 414Ex CCD, ZWO ASI120MM guide camera with WO 50mm guide scope, Astronomik Ha 6nm filter).
I will post my actual setup for this one soon--mainly because I want to lock down my portable gear for reference when setting up in the field. What amazed me tonight was the ability to get pretty clean 20-minute subframes with the new iOptron CEM25P mount, leveled, pointed toward the NCP, and a quick polar align. And all of this on the back deck, which isn't the most stable platform around. (There is some star elongation at the top right and bottom left corners, which I'm attributing to the image train and focuser sag. It's slight, but it's there. My next large-ish purchase for the GT-81 is a Moonlite focuser, which will significantly improve the rigidity of the system).
I have to say I am really impressed by the CEM25P mount (the latest iteration of the ZEQ25 from iOptron), and I was expecting quite a bit of precision given that the company pretty much guarantees a low periodic error (< ± 10 arc seconds). But to have this come through without even trying...well, that makes me happy.
Posted October 2, 2017
Astro Setup - September 23, 2017
What the backyard looked like last night. Sort of an astronomy campout under the stars. It was a pretty clear night. I hope you had clear skies wherever you were last night! (Nikon D3100, 18mm, 13 sec. exp. ISO 1600 - I used my son's camera for these shots because mine was hooked up with the AstroTech scope)
Here's one from last night's astro shoot: M42 - Orion Nebula (Yes, my favorite diffuse nebula). This time of year Orion doesn't start appearing over the horizon until the early morning hours. My Exposures started around 2am and ended around 5am. (Nikon D750, AstroTech AT6RC, William Optics field flattener/ 0.8x reducer; 162 light frames stacked in DSS, 140 dark frames).
And another shot from last Saturday night--of the Orion Nebula (M42) and De Mairan's Nebula (M43). This was the view from my other scope, William Optics GT-81 with the Atik 414EX monochrome CCD camera--which is just going to pick up a lot more of that good old ionized interstellar hydrogen.
Posted September 23, 2017
Solar Photography - August 21, 2017
My contribution to the 2017 Solar Eclipse craziness. I shot nearly 200GBs of video and still images with a QHY5III178 CCD camera, Nikon 300mm lens, Seymour Solar filters.
I did manage to pick up some decent sun spots on all the filtered images:
Solar eclipse and moon composite shot:
Here's the simple setup I used for these solar shots: QHY5III178 CCD camera, Geoptik Adaptor for Nikon lenses, Nikon 70-300mm lens, Seymour Solar filter. I used SharpCap under Windows 10 to capture frames. And before you ask I'll say, yes, I am using dew heater strips to hold on the solar filter, which is sized for 4.1" diameter scopes (like the William Optics GT-81). And yes, that isn't very safe if I was looking directly through the lens, but since I was doing all of this from the shady comfort of my garage...well, that's okay then, right? Sometimes you just have to rig something up to take some pictures.
Posted August 21, 2017
Remote Astro - July 24, 2017
I'm down with the LMC--let me hear you say Large Magellanic Cloud. I took some wide field images of a small portion of the LMC, centered on the Dragon's Head Nebula (NGC2035), that colorful stretch of star-forming cloudiness in the middle of the pic. Astro specs: 8 stacked 300 sec exposures, Takahashi SKY90 APO, SBIG ST2000 XMC camera, Paramount PME.
Now, before you go thinking that I've teleported to the southern hemisphere, which is where you have to be to see our nebulous galactic neighbor, the Large Magellanic Cloud, I assure you I haven't. I have merely bought a tiny slice of observatory time on some fantastic hardware that happens to be located at the Siding Spring Observatory, New South Wales, Australia.
I will also tell you that I can fly from here to Australia seven or eight times--first class--for what that equipment setup costs. It's so much easier pretending to be there under the stars near Coonabarabran, using some totally badass astronomical gear. And it's easy, and inexpensive. Besides, it's pouring rain here, and I miss seeing the sky. Wait, I don't have to justify my imaginary stargazing trip to Australia to you! Go check it out yourself: https://www.itelescope.net (The observatory in Spain is lovely as well).
A portion of the Large Magellanic Cloud
