My homebrewed z-axis counterweight for the iOptron GEM28 mount.

iOptron mounts (at least my GEM45 and GEM28 mounts) can be a little finicky balance-wise because they turn so freely and easily on their axes when the locks are disengaged. I’ve found that I get the best performance with these mounts when I balance them in RA and declination and then also on the so-called “z axis”. When I first heard about z-axis balancing I was a bit skeptical and didn’t really understand what it was or why it was important.

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The Helix Nebula (NGC 7293)

While my C8 was busy last week grabbing photons from the NGC 7331 Group of galaxies, my travel imaging rig was busy staring at the Helix Nebula. This setup, a Sky-Watcher Evolux 82ED refractor (with reducer) on an iOptron GEM28 mount, is quite a bit more portable than my other equipment and is something I can tuck into our RV for travels. I can shoot either mono or color with it, even narrowband. This shot was taken using an Optolong L-eXtreme dual narrow-band filter with an ASI533MC Pro OSC camera. I managed to grab 7.5 hours of 5-minute exposures over two evenings (I can only shoot this target for about 4 hours a night from my location). I processed it in PixInsight and Affinity Photo, but I didn’t try to do any pseudo-Hubble palette this time. It’s not an ideal target for a small refractor but it turned out okay.

The Evolux 82ED seems like a serviceable refractor, although it’s only a doublet. I think the optional 0.9x corrector is really required equipment for imaging, and shooting narrowband helps to hide any remaining flaws. The iOptron GEM28 is a nice little mount. I initially had some intermittent problems with it (it would stop tracking for no reason) but I think a faulty USB cable was to blame. Guiding isn’t perfect but I can generally get 1 arc second or better.

The NGC 7331 Group

When it looks like we’ll have clear nights with little to no moon, it’s time to set up and shoot some more astrophotographs. Last week we had two such nights, and both nights I had two imaging rigs going at the same time (a bit of a juggle, to be sure). My C8 with Starizona SCT corrector (on my GEM45 mount and concrete pier) was busy capturing this beauty, NGC 7331 and its neighbors, comprising the NGC 7331 Group. I shot this in LRGB using my ASI533MM Pro camera and Optolong LRGB filters. PixInsight and Affinity Photo were used to process the image. I was able to capture about 9 hours of 3-min exposures (31 in red, 26 in green, 31 in blue, and 91 luminance).

My C8 has turned into an astrophotography workhorse for me. I always use the Starizona SCT corrector to get a nice flat field. I find myself using this setup more than I anticipated. I got the C8 OTA as partial payment for some freelance coding work, and at the time I wasn’t sure how much I’d use it. So I’m pleased it’s been so useful for targets like this one. Don’t get me wrong–I still love my refractors, but they specialize in the larger targets. There is no “one telescope to rule them all.”

You can see more info about this image on my Astrobin page:

The Dumbbell Nebula (M27)

Finally had another clear evening with a dark sky so I fired up the C8 and shot the Dumbbell Nebula, a planetary nebula in the constellation Vulpecula. I shot this in LRGB and Ha using my ASI533MM Pro mono camera. I also used a Starizona SCT reducer/corrector so the net FL was 1469 mm. I’m glad I grabbed some Ha on this target because it really made the red color pop. I captured 14 180-sec subs using the R, G, and B filters, 28 120-sec subs with the L filter, and 14 300-sec subs with the Ha filter. Processed using PixInsight and Affinity Photo.

With autumn approaching, the nights are longer and the weather here in the mountains of Colorado gradually yields more clear nights. Combine that with a waning crescent moon, and I had two nights to shoot a new target. This time I shot the Ghost of Cassiopeia (IC 63) with my ZWO ASI533MM Pro camera through my Sky-Watcher Esprit 100 refractor, using L, R, G, B, and Ha filters. This target is a bit challenging to process due to its close proximity to Navi (gamma Cassiopeia). Processed using PixInsight and Affinity Photo. I was able to collect almost 13 hours of data on this target. I took 3-min exposures in L, R, G, and B, and 5-minute exposures in Ha–a total of 39 exposures in R, 38 in G, B, and Ha, and 77 in L.

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I’ve been trying to figure out an issue I’ve been having with my iOptron GEM28 mount, and the log file produced by iOptron Commander contains a lot of information that might be helpful. Unfortunately, it’s not terribly readable, so I wrote a Windows application to convert the log file into a more readable form. Here’s a video demo:

You can see all the details, and download a copy for yourself, here:

iOptron Commander Log File Viewer

The other day I was working with one of the Bluetooth digital setting circles boards from FAR Circuits, and I was having a hard time getting the board to pair with my new Dell laptop running Windows 11. No matter what I tried, I couldn’t get the Bluetooth board to be discovered by Windows 11. I tried two other Windows 11 laptops and had the same problem. Then I tried a Windows 10 laptop and it paired just fine. So what’s the deal?

Well, after trying a bunch of stuff, doing a lot of Googling, and even enlisting Windows tech support, I finally stumbled upon the solution to this problem. For whatever reason, Microsoft decided to add a new Bluetooth setting in Windows 11 that changes the way that Bluetooth discovery occurs. You’ll find it in Settings -> Bluetooth & devices -> Devices in a setting titled “Bluetooth devices discovery.” This setting has two possible values: “default,” where only common types of devices will be discovered, or “Advanced,” where all Bluetooth devices will be discovered. This setting must be changed from “Default” to “Advanced” in order for the Bluetooth digital setting circles module to be discovered in Windows 11. Thanks, Microsoft.

I updated my Bluetooth digital setting circles setup and configuration guide with this latest information.

Fleming’s Triangle in the Cygnus Loop.

I recently found both the Sky-Watcher Evolux 82ED telescope (and its flattener) and the iOptron GEM28 mount on sale for significantly off their regular prices. I was looking for an upgrade for my portable imaging setup (we live in our RV for a few months each winter in warmer climes) and this seemed like a good candidate. I hate not being able to image in the winter–the nights are long and clear and the skies are abundant with great targets. So, I pulled the trigger.

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The Hercules Globular Cluster (M13).

Some nights of imaging just don’t go quite the way you planned. I was planning to shoot a different deep-sky object this particular evening, but my off-axis guider was improperly configured due to my own ineptness, and guiding (the process of making minute corrections to the mount’s tracking while shooting an image) was just not working. Rather than fumble around in the dark in the middle of the night, I decided to see if I could shoot shorter unguided exposures and still get something out of the night.

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The Cat’s Eye Nebula, NGC6543.

With finally a stretch of a few nights with clear weather here in June, I managed to shoot a few new targets. This one is the Cat’s Eye Nebula, and I shot it with my Celestron C8 using a Starizona SCT reducer/corrector for a net focal length of 1469 mm. This was shot in color using my ASI533MC Pro one-shot color camera. I shot 45 5-minute exposures and processed them using PixInsight and Affinity Photo.