[Therion] Disto-X Calibration Woes

Footleg drfootleg at googlemail.com
Mon May 4 15:51:59 BST 2009


I did a similar calibration in a small stand of trees one lunchtime
near where I work. I think the important thing is to ensure you have
the back of the disto held on a fix point, and the laser pointer on a
fixed target for each of the 4 readings per barrel roll of the device.
Choose trees with a spacing of 4-5m to get the most accurate readings.
I followed the instructions and took all 56 readings representing the
directions from the centre to the 6 faces and 8 corners of an imagined
cube. It is only the directions which are important, so you can move
the disto to a different tree to get each set of 4 readings. Assuming
your DistoX is not faulty, this should give a good calibration. I got
0.25 on my second attempt.

Footleg

2009/5/4 Bruce Mutton <bruce.mutton at paradise.net.nz>
>
> BTW, the best way to callibrate DistoX is to find in a forest THREE
> trees 2 m each from the other representing "half of cube".
>
> A->B
> B->A
> B->C
> C->B
>
> C->base of B
> C->2 m height  of B
> B->base of C
> B->2 m height  of C
> B->base of A
> B->2 m height  of A
> A->base of B
> A->2 m height  of B
> up to your upset hand
> down to your feet
>
>
> Martin
> I assume B is the 'right angle' corner of the triangle formed by the trees.
> In this case, if I understand you correctly, you have described directions
> that are much more biased to particular orientations than Beats instructions
> (The diagonal plan and sloping directions are omitted).  The instructions do
> say the particular orientation is not important, but given the troubles I am
> having I would have thought a uniform three dimensional spread described by
> cube faces and vertices would be less risky.
>
> On the other I can see it is easy to implement in the field without any
> special equipment provided one can brace the disto-X against the tree and
> not bump it when the button is pressed.
>
> I'll give it a go.
>
> Bruce
>
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