Carlson Quarryman Pro, User Manual

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The
Chord setting requires you to select a chord distance in metres (or feet if you are using Imperial units). Enter
this value in the FastScan settings screen.
A chord should be used for most operations, as it is much harder to envisage the actual line spacing at a given
distance when using an angular arc value. For example, if the unit is 100 m from the face, what would the line
spacing be if a 0.2° arc spacing was entered? It would be easier to enter a chord of 0.35 m and let the instrument
make the appropriate calculations to determine the required angular movements between scan lines.
If
Chord is selected, the Quarryman Pro laser module will use the initial single shot – taken after defining the scan
window – to calculate the angle that will need to be subtended in order to achieve the user-defined Chord value on
the face.
Note that the single shot should be taken in the middle of the scene to be scanned, as this will give a rough average
calculation for the whole scene. Once calculated, the same angular increment is used across the whole scan and
is not adjusted if different parts of the targeted scene are at different distances from the Quarryman Pro. If the single
shot is taken at a part of the scene that is very close to the instrument, the line spacing for areas further away will
be increasingly large. If the shot is taken to a distant part of the scene, the line spacing will be increasingly small for
areas closer to the instrument.
Irrespective of the entered
Chord value, the minimum angular increment that the Quarryman Pro will operate at is
0.05°.
Figure 45 FastScan with Arc increment selected
Arc value
selected to
determine scan
line spacing