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    Re: Measuring (and Calculating) Dip
    From: G Becker
    Date: 2013 Jul 5, 13:27 -0700

    The attached pdf file is a nice example of the "flip the scope" method.


    For the American transit, I had vaguely remembered that in the "ole days" there were procedures to flip the scope, turn angles right, turn angles left etc. I never did any of these things because I've never done highly precision work as required for a land survey, long distance surveys, or legal documents. I'm a civil engineer that does very simple / ordinary construction layout, mostly as a volunteer for Rail Trail work. Once I bought an EDM/theodolite the precision and accuracy was so much greater that specialized procedures became totally unnecessary for me.

    However, for measurement of small vertical angles, technique becomes very important. My plan is now to set up the theodolite, make a set of readings "wire" coming down; another set wire going up. Flip "gun" 180*, rotate 180* and redo. I honestly don't remember how my internal optical angle scale functions in the "reversed" mode ie, whether the sign of the angles will be greater or less than the previous mean value. Maybe doubled? I'll go read the manual and a good surveying book. Your comments are appreciated and I think saved me some work while increasing precision and total accuracy.



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