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    Re: Finding IC for A-12 bubble sextants
    From: Art Leung
    Date: 2021 Oct 7, 06:26 -0700

    David Pike wrote: "3.  Take numerous sights approaching from either direction and average them, but don’t have them too far apart at meridian passage (why not?)."

    I typically average when the object is away from meridian passage.  Even then, a quick series of shots means less change in the object's actual rate of altitude change over time - I will do 7-8 shots in 4 mintues or so with good results.  Near meridian passage I will shoot a series quickly over a longer period to see both the rise and fall so I can figure the time of local noon with a reasonable amount of accuracy.

    At least, that's how I have done it but I can't claim to be a professional navigator!  I do this from my backyard and it's not moving - the practice is fun and my goal is very high accuracy.

    Doug Faunt wrote: "Do you think your friend would be willing to do another mount for me?"

    I suspect he would but it might not be cheap.  The mount takes up a fair amount of material and takes quite a while to print.  However, I will ask.  I know that he would be willing to share the raw input files so if you have a 3-D printer or access to one, it would get you there.

    Pictures of the mount included.  If you are interested, my personal email is cnavSpica at protonmail.com

    -- Arthur




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