You should recalibrate the device if ambient
conditions have changed. This applies especially
when changing location if major changes in
temperature and relative humidity may be expected
as a result (for example inside/outside).
When moving from cold areas to warm areas, there
is a danger of condensation. For this reason, after
there has been a change in ambient conditions, you
should wait for an appropriate amount of time to
allow the optical components to adjust before
calibrating and using the unit.