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Measuring precision from discrepancies between setout points

Using a measuring tape, measure the distances between the physical marks in a shared axis. These should multiples of 1m (metric) or 3’ (imperial) apart. Precision is determined by the discrepancy between the measured distance and the grid size and should be highest when nearest to a marker. Precision will reduce outside of the boundary defined by Markers (or away from the axis of linearly positioned markers) and may not be uniform throughout your space.

Factors affecting precision in the test

The proximity of the crosshair to a Marker, human error in marking out from the crosshair and human error in measuring distance between marked crosshairs will all affect the discrepancy of individual measurements. Some areas of the workspace may track better than others due to environmental factors, and some Markers may be more accurately located than others and so measured precision may not be uniform throughout the test.

Maximum precision

If your marker distribution allows you to perform the precision test while being within 2000mm of a marker and within a boundary defined by markers, all markers are accurately positioned to 1mm and the workspace has been set up to be optimal for HoloLens tracking you should expect measured differences to be 0-3mm due to human error and the fidelity of the HoloLens display. If working with fewer markers (resulting in greater distance from markers while performing the precision test), or if markers cannot be reliably located (for instance by being approximately located on the surface of physical objects) then you should expect some increase in measured differences.

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