Telescope cleaning & collimation test

 03/08/2025 -- Cleaned the corrector as well as the primary and secondary mirror on the venerable Meade LX10 SCT. Also cleaned the surfaces on the Svbony Sv405cc, the UV/IR cut filter and the Starizona SCT corrector III using generic lens cleaning wipes (Costco/Amazon) and the ancient lens cleaning kit blower & brush.  Struggled with streaking and dust... but eventually got to a point where improvement was clear (especially for the SCT corrector and the secondary.  Tested outdoors with the OTA reassembled and found major dust / dirt problems were solved.  Tested collimation against a bright 1st magnitude star and found no issues (thankfully). Defocused pattern looked symmetrical.  Tested using AstroDMX-Capture on the Odroid C4 viewed over Remmina RDC client (using the UV/IR cut filter...broad band imaging). Captured the moon and then switched over to the dual narrow-band (OIII, Ha) filter...since the moon is up at 79% all night.  Attempted to get the Owl nebula (M97) as a test collection with the cleaned optics but struggled to get the OTA into position with plate solving.

Seeing forecast from cleardarkskies captured at 12:10 on 3/9/2025 showing overall fairly clear skies but a large moon impacting darkness.
Ultimately, plate solving failed repeatedly for 3/08, 3/10 attempts to capture light frames.

03/11/2025 -- Clear skies (early) but the moon is high in the sky at 93%...tonight is only usable for testing purposes.  Indi Allsky backyard camera showed a pseudo sky quality metric of ~23,700 in moon mode (gain limited to 75%) at 23:30 (where 4,000 would be a reasonable value w/o the full moon). Fiddled with plate solving settings in Indi/Ekos ... challenging with the dual-narrow band filter in place and poor contrast in the sky. Found a set of parameters that appeared to work.  Also noted the the autofocus routine appeared to be at maximum inward travel without achieving fine focus. Used a laptop and adjusted the primary mirror against a bright star to bring the OTA into focus manually.  Set up M106 in the scheduler as a test object.With temperatures still at 50F at 23:30, used the cooler to put the SV405CC camera down to 0C.

Seeing forecast from clear dark skies for 03/11 looking grim wrt clouds later in the morning of 3/12 (European model) as well as poor darkness with the giant moon.

Seeing forecast for 03/11/2025 from meteoblue suggesting some clouds (low, medium & high) starting at 02:00. Plus huge moon.



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