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    Re: Longhand Sight Reduction
    From: Francis Upchurch
    Date: 2014 Nov 18, 22:56 -0800

    Thanks Hanno,

    They look fine to me.Very clear and easy to use.Congratulations on all this.

    If interested, see my recent postings on the Brown-Nassau graphic circular rule for LOPs. I think this may be faster than the Bygrave and apparently accurate to 2.6' of arc. Nobody seems to have seen one of these, so I guess I'll just have to try and make one from the limited information in the 2 papers. Do you or anyone else have the knowledge/skills/time to produce computer generated quadrant curves based on the basic spherical trig equations cited in the Brown paper?

    If I cannot get those, I'll try to use the graphs from the paper. Perhaps they can be edited with photoshop or other graphic software? Can anybody out there  help?

    Best wishes



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