Midland Valley FieldMove Clino, Руководство пользователя

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Digital Compass Calibration
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We have found that some devices do not correctly report inclination. This is obvious when a
device is on a flat horizontal surface, yet FieldMove Clino still reports a dip. We believe this
is due to components in the device not being seated properly, as we have tested other
devices of the same make and model and not observed any problems. To counteract this,
we have added an accelerometer calibration option in the app settings. In all cases,
calibration resulted in devices correctly reporting inclination.
To get the most out of your smartphone we recommend that you collect data with the
device in a variety of orientations and compare this against a traditional hand-held compass
clinometer to work out the best orientation to collect data in. Many Android devices work
better when held against the rock in landscape mode (long-axis horizontal) rather than in
portrait mode (long-axis vertical). When measuring lineations, some Android phones will
only record sensible measurements of plunge azimuth in one orientation - when the device
is held with the top of the screen pointing down- or up-plunge depending on the
manufacturer. This does not seem to apply to the iPhone (all models) with good data being
recorded irrespective of the orientation of the phone.
These questions may help you:
 Does the phone have reasonable consistency with itself in all orientations and
situations?
 Does the phone have reasonable consistency with a control analogue compass-
clinometer in all orientations and situations?
 Are there any orientations (e.g. device long-axis vertical or horizontal) that provide
more consistent and accurate results? If so, make sure to collect data only in these
orientations.
As with an analogue compass, be aware of sources of interference. This can come from
magnets, ferrous metals, electronic devices, another analogue compass or electronic device,
watch or phone case (beware of magnetic clasps) to name a few.
..and finally
FieldMove Clino is designed to make data collection quick and easy, facilitating the collection
of large, statistically valid data sets. We have found that there are tremendous advantages
to using FieldMove Clino on a well-calibrated smartphone. Most users will have experience
with traditional analogue devices, where often a single reading at each station is taken with
the assumption that each of these readings will have a high level of both precision and
accuracy. This assumption is normally wrong. We always recommend taking several
readings at each location, which can then be treated statistically to provide both improved
accuracy and an understanding of measurement error.