Celestial hemisphere:  Southern  ·  Constellation: Ophiuchus (Oph)  ·  Contains:  10 Sgr)  ·  19 Sgr)  ·  20 Sco)  ·  21 Sco)  ·  22 Sgr)  ·  23 Sco)  ·  35 Oph)  ·  35 Sco)  ·  42 Oph)  ·  Al Nasl  ·  Al Niyat (σ Sco  ·  Al Niyat (τ Sco  ·  Al Thalimain (λ Sgr  ·  Alniyat I  ·  Cor Scorpii  ·  El Nasl (γ Sgr  ·  IC 4604  ·  IC 4605  ·  Kalb al Akrab (α Sco  ·  Kaus Meridionalis  ·  Lagoon Nebula  ·  M 20  ·  M 4  ·  M 8  ·  Media (δ Sgr  ·  NGC 6121  ·  NGC 6514  ·  NGC 6523  ·  NGC 6526  ·  Nash  ·  And 18 more.
Tales from the Core, and a glance at Rho Ophiuchi cloud complex, Mihail
Tales from the Core, and a glance at Rho Ophiuchi cloud complex
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Tales from the Core, and a glance at Rho Ophiuchi cloud complex

Tales from the Core, and a glance at Rho Ophiuchi cloud complex, Mihail
Tales from the Core, and a glance at Rho Ophiuchi cloud complex
Powered byPixInsight

Tales from the Core, and a glance at Rho Ophiuchi cloud complex

Equipment

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Acquisition details

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Description

There are times when everything runs smoothly, and times when one would want to set their mount on fire. There are also times when said mount overhears this, gains consciousnesses and turns on the sprinkler system as a preemptive attack, soaking the entire rig in the process. This is a tale of epic failures, but also of great lessons learned.

Checked-in luggage 1: 22.5 Kg
Checked-in luggage 2: 16 Kg
Backpack with camera, lenses, laptop, power-banks: >20 Kg
Me trying to hide that the backpack is heavier than my 10yo kid during onboarding: priceless

So we planned to visit the Canary Islands again, this time in spring (indeed it's a paradise) - we selected two previously-unexplored islands: La Gomera and El Hierro. I checked Stellarium with the coordinates of our locations and date interval to see if there's anything interesting to be seen which normally is obscured by our northern horizons, which was apparently *Mistake number one*, because I got over-enthusiastic that I would be able to see some of the Southern Sky jewels.
So I pack the Z6, 3 lenses, a huge power-bank and a smaller one, laptop, kilometers of cables, the smallest guide scope and the guide cam, the old ASI Air + wireless extender and I wondered about the mount for all this stuff. I had just received and tested the AM5 harmonic mount, and it was so easy to set up, but the mount and its tripod are quite heavy, so when I started packing, I realized that I'm going way over weight budget. So two days before departure I enter damage mitigation mode, and decide to take the old Star Adventurer (**Mistake number two**). I read up on if the SA can be guided via the ST4 port, and in theory it can, so without any testing, I just pack everything and hope for the best.
To mention: one of the lenses included is the Tamron 70-200 F/2.8, which I ordered just a week before departure. I was lucky to receive a good-quality copy, with decently-corrected aberrations.

First stop was Gran Canaria, landing after midnight, we had to book a place to sleep. I just tested the 70-200 lens, very good performer, but the stabilization mechanism eats the battery like crazy. Good thing that it'll be disable for astro use.

Second stop was La Gomera. We stayed in a Casa Rural (rural house), in a banana field, with a small garden more or less shielded from street lights, but I had miscalculated the slope of the steep volcanic mountain, so I had no horizon to East, South or West. With Milky Way so low this time of year, I had to resort to testing the equipment and shooting the Markarian's Chain of galaxies (photo TBA). I tested how the ASIAir pairs with the SA mount via the ST4 port, learned that the calibration works, but only in RA axis (d'uh), contrary to some online posts which mentioned that one shouldn't erase the calibration because it won't be able to re-calibrate ever (perhaps this was fixed in newer versions).
I also tried to do Polar Align using the ASI Air (***Mistake number 3***) - lost 2 hours in the process of avoiding astro-yoga, until I realized that the mount Alt-Az controls are so bad, the backlash somehow translates to both axes and it's much better/faster to do it the classical way (Polaris View app and astro-yoga). By the time I polar aligned, calibrated and did the first guide tests, the clouds rolled in. I dismantle everything and go inside thinking about how flammable a mount would be. Next morning I notice wet grass (must be dew).
Another two cloudy nights, time for frustration to build up... The fourth night: finally clear-ish skies; I finish family duties in unprecedented efficiency, and set up the trembling rig when I notice that the screws holding the Alt-Az mount base are very loose, thus explaining the polar align antics I just went through. Mental note to glue those screws when back home. After a quick fix, yoga-PA, calibration and focus with the tri-bahtinov (why did I have to get that instead of the simple one? much harder to use), I finally start to image. Since the AIR has horrendous Wi-Fi capabilities, I plugged in the Vonets extender. Checking two hours later, I realize that the whole rig + dew heaters draws quite a lot of current, thus depleting the power-bank, so I gather everything up and head back inside.
Last night on the island, also clear skies, so I decide to perfect the power management so that I'm ready for the southern-most trip; I decide to disable the dew heaters since the humidity was really low, set up the rig with some sunbeds to shield it from the herd of cats living in the area, and let it image overnight so that I get some sleep. The next morning, I realize what an epic mistake that was... the "dew" was actually automatic hidden sprinklers that completely soaked the rig. It's impressive that it was still running when I woke up, but the power supply died shortly after. (insert Andersen-esque short film-cut of bowl with rice and a screwdriver) cleaning the circuit board of crystalized green stuff, I realized it's a good thing that the camera was environment proof, otherwise I'd be out of business for the rest of the trip. The lens however was less water-proof than advertised, but after a day with the dew-heater around it dissipated the cataract-like condensation on the inner-side of the front lens. Everything was working again and an epic Phew moment passed.

Third and last island was even more remote, and this time the lodging was in a completely dark area. After shutting off/covering the solar lamps, SQM measurements showed 21.4 magnitudes/arcsec^2 - not the best I'd seen, but more than decent. The problem was that it was permanently cloudy, even though the meteoblue meteogram featured pristine clear skies. The fourth night had some gaps in the clouds, so I decided to try my luck, but again, after setting up, the clouds rolled in. With only 3 more nights until departure, I was getting nervous, thinking that I carried so much equipment and almost drowned the rig only to return with some tiny galaxies that I could have shot from the backyard at home...
Second-to-last night: finally some clear skies. Of course, it was quite a big first-quarter moon, so set up the rig and then I set up my watch to wake me up at 3 AM to start shooting the interesting stuff down south. Upon waking up, I come with the idea that maybe, just maybe, I can take a glance at the Omega Centauri, the king/queen of globular clusters. To my surprise, it was visible visually, even with the setting moon not quite below the horizon, but the rig was too low to image it as well (it would have been too small of a target to do it justice anyway). So I reverted to the main plan to shoot Rho Oph cloud at 200 and 70mm focal lengths. 200mm session having finished, I decide to capture also the galactic core, until I realize that there are electricity cables in the frame. Well, too late to move the scope in sleep-deprived conditions, I maxed out my tries on luck on the previous island, so I decide to shoot and let the integration rejection algorithm deal with it. Another mistake, of course, because the next morning I checked the subs, and the cables were running precisely along the RA axis, and removal would have been impossible without butchering the image.
Last night, last chance. Even though we had to leave early and I would jeopardize the luggage operation, I decide to move the scope to another position, cover a streetlight with garbage bags and try again. Watch set again to wake me up at 3 AM and...the.mount.would.not.track... The infamous blink of death was upon me. I remembered that last time the issue was due to misaligned photodiode on the motor encoder, but there simply wasn't enough time to dismantle the mount and precisely re-align the emitter with the receptor, so I decided to try forcing it to disregard the optical input by intentionally dis-aligning along the RA axis and then starting the guide immediately after turning on the mount. I cannot believe my sleep-deprived mind, but it worked. Waited 10 subs to complete to see the inevitable blink of death occurring again, but it just kept tracking - with an RMS error of 12-15", but could have been worse.

So now, after two weeks of carrying stuff like in Death Stranding and almost ruining the rig, I present my first try at imaging our galactic Core. It's by far not perfect, but it was a roller-coaster ride.
BTW, the mount was repaired and I'll now sell it to replace it with an AM3. The 24-70mm lens is still de-collimated, so I lugged it unnecessarily. The short-range ASI Air will be replaced by the mini version with external antenna and I'm thinking about modding the Z6 or getting a dedicated cooled DSO color cam.

Stay tuned for more astro-antics!

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