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Celestron CGEM Meridian Flip Testing

 03/19/2026 -- No moon, but lots of clouds (more than predicted) makes the evening a good opportunity to play with the Celestron CGEM DX with the Nexstar+ version 4.22 hand controller and Indi/Ekos with regards to meridian flip.  Numerous / repeated disasters where the scheduler is paused ... in some cases for a half hour...other times for hours (never recovering) from repeated attempts to deal with meridian flip...almost always looking northward (since the deck is facing polaris).  Read the Stellarmate guide on meridian flip... which while helpful, does not necessarily provide clear guidance specific to the Celestron...but it does illustrate how this process _should_ work.  Re-read the overview on the Celestron NexStar Indi driver ...which is outdated and does not really deal with the interplay between driver, Ekos / Indi meridian settings and hand controller RA limits and meridian settings.  Also read the original Celestron User Manual for the CGEM , which do...
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NGC 3184 / M94

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 3/8/2026 -- Clouds are gradually clearing out and the moon is not set to rise until after midnight...so working to capture light frames from a well-positioned galaxy -- NGC 3184.  Checked polar alignment with PHD2 running on the Odroid C4...drift alignment showed near 0 error (after an extended period of drifting).  Due to sudden heat wave (to 70F), manually adjusted the focus (turned primary mirror focus knob left 1/2 turn, total).  Seeing forecast for 03/08-09/2026 from meteoblue (top) and cleardarksky (bottom) suggesting clearing skies through midnight...with the moon appearing after 00:49. Set up the scheduler with NGC 3184 collecting UV/IR light frames through 01:35 and M94 collecting until 05:45.  Set the chiller on the Sv405cc to 0C to match existing calibration frames but also since the temperature is predicted to fall to 45F overnight. Overnight, 80x80s NGC 3184 light frames and 59x80s M94 light frames were collected.  After a lengthy (30 minute) ...
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NGC 2903

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2/27/26 - No clouds, giant moon (82%).  Because of the size and duration of the moon (all night), narrowband imaging is really necessary... but there are limited targets in view.  Noted M97 is at a favorable position.  Seeing forecast for 02/27-28/2026 from meteoblue showing almost no clouds but large persistent moon. Seeing forecast from clearoutside for 02/27-28/2026 showing favorable conditions overnight. Starting around 20:00, launched a polar drift alignment in PHD2 running on the Odroid C4 desktop over RDC.  Started at ~28' and after two adjustments (to the left, pre-meridian flip) brought this down to 0.26'.  Ran an autofocus in the background with the venerable Meade zero-shift autofocus hanging off the Shoestring Astronomy controller. Reached a minimum HFR of 3.76 after six iterations.  Low temperatures were expected near freezing and so set the SVBony Sv405CC chiller at 0C. After slewing to M97 and starting the focus routine, noted that it's still...
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Broadband Imaging - NGC3184 / M106

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 2/13/2026 -- No moon, no clouds (until 05:00)...clear, cold skies.  Time for some broadband imaging on galaxies in view.  Evening started with relatively poor skies (pseudo sky quality metric of ~9200 at 21:00).  Configuration unchanged with the Celestron CGX DX mount, Meade LX10, Starizona Corrector III (0.63 corrector and reducer), Xagyl filter wheel, Svbony 405cc (chilled to -7C). Seeing forecast for 02/13-14/2026 from meteoblue (top) and clearoutside (bottom) showing clear skies expected until 05:00 and no moon. Initial drift alignment in phd2 running on the Odroid C4 showed an alignment error of ~9'. Not bad, considering it's been sitting for weeks through strong winds, snow, etc. with the cover on.  First adjustment (to the left) over-corrected...with an error of -7'. After several adjustments back & forth...ended up below 1". Set up the scheduler for light frame collection on M106 through 05:35.  Sequence file configured with gain 285, offset 24...
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Testing a Dark Filter in the New Year

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 01/28/2026 -- bad skies, cold temperatures... so far only a few opportunities for imaging in December of '25 and January (so far) in '26... and tonight is not really much better. Giant moon, poor-ish skies... but took the opportunity to finally pull off the covers and test out a new totally dark filter (black) from Svbony that may aid in collecting dark and bias calibration frames at the end of a session. Installed the new black filter in the Xagyl 8-position filter wheel (now with position 1 == UV/IR, position 2 == dual narrow band (Ha/OIII) and finally position 3 == black). The Indi allsky backyard camera pseudo sky quality metric is grim (even in "moon mode") with a value over 37k at 22:31.  Save a copy of the outdoor weather station JSON report at 22:20 and noted lovely conditions (to include light wind): "time": "2026-01-28T22:20:00-0500", "generator": "weewx 5.2.0" "temperature": {"value": 19....
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