Koehler Urban Astrophotography

 10/21/2024 -- Clear skies but a big moon (79%) coming up at 22:30 motivated an experiment with the dual narrowband (Ha/OIII) filter on the LX10 with the Starizona SCT Corrector III and the Svbony 405cc. Seeing forecast from cleardarksky for 10/21/2024 showing clear skies, good transparency but bright moonlight. Seeing forecast for meteoblue showing similar trends. Spend 1.5hr polar drift aligning... painful...back and forth. Then spend 30 minutes on focusing...with the dual narrowband filter in place. Then searched for bright nebula still visible despite trees from the back deck. Settled on IC 5146 (Cocoon Nebula). Started the internal autoguider... which calibrated fine...and began 180s test image. Created a job in the Indi/Ekos scheduler for IC 5146 with 180sx20 at 5C, gain of 285 and offset 32 in a sequence file to repeat until 05:30. Promising initial result -- one light frame (180s x1) with gain 285, offset 32, temp at 5c stretched in the Indi/Ekos FITS viewer. Collection of ...

 10/13/2024 -- Configuring the venerable Meade LX10 2000mm/F10 SCT with a new 2" visual back and the Starizona SCT Corrector III.  Set up spacers to ~1mm of the 83.8mm backfocus needed with the Svbony 405cc camera (based on a total required backfocus of 90.3mm for the SCT Corrector.  Skies were very poor with huge moon and clouds... but was anxious for first light to see how this new corrector performed.  The mount was nominally polar aligned from previous work (10/12) with the Celestron 10" newtonian attempting to fix collimation (only partially successful).  Reworked the counterweights and checked the balance of the LX10, spacers, RACI guider with Zwo ASI120MC-S and SCT corrector.  Then worked to achieve focus... which was ultimately successful (after cranking the focus to the left substantially).  Views of stars in the M31 area looked uniform and round across the whole field.   Set up a job in the scheduler for the center of M31 with 80x40...