When is an altitude calibration necessary (instrument setup)?
For most of the applications, this function is not required. Where the difference in altitude can be measured with a measuring tape or folding rule, it should be proceeded this way. The altitude calibration changes by a few per mil (1..2) according to the region or over a long time period as well. Only if altitude differences accurate to the millimetre are to be obtained, an occasional check of the altitude calibration is recommended. Two vertical line up points with exactly 1000 mm altitude difference (1m-water level, 1m-pieces of timber) are suitable for this. A coarsely adjusted altitude calibration can be reset to the factory setting per ->Sett -> r. The altitude calibration always uses millimetre!
