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    Leveling mirror with plumbob
    From: Örjan Sandström
    Date: 2012 Mar 31, 15:47 -0700

    I have tried the trick mentioned regarding levelling a mirror using a plum bob.
    as far as I can tell it works if string is thin enough preferably braided and has a well centred attachment point like the ones used in surveying.

    The trick seems to be holding string still while dialling the thing level and looking at the string such that one can see string near bob and reflected image of string going from hand at same time, as string is 0.2mm diam and roughly 1.5mm long when it is one continuous line it is within those 0.2mm over the 1.5m -if I made my maths right- that means level to roughly 30 seconds of arc.
    can anyone confirm this?

    I will send image of string, bob and mirror tomorrow, too dark outside now to see the string on the images.


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