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3.6.2 Calculate Atmospheric Correction out with
temperature and pressure sensor
First, pre-measure the temperature and pressure of the
surrounding at the measured station.
e.g. Temp: +25
℃
atm:1017.5
Press soft key „Enter‟ to move inserter to the „Temp‟
column and type in „25.0‟;
Press soft key „Enter‟ to move inserter to the „Press‟
column and type in „1017.5‟;
Press soft key „Enter‟ to move the inserter to the „prism c‟
column;
(the„PPM‟ column now displays 3)
Press ‟ENT‟ to save the parameter setting. Our system will
display „Record: ***(name of the point)‟ and quit the dialogue
box. The point is now saved.
3.7 Correction of Atmospheric refraction and Earth
Curvature
When measuring horizontal distance and elevation, our
instrument is capable of correct the atmospheric refraction and
the earth curvature.
The formulae of the two corrections of our instrument are
as followed:
Measured Horizontal Distance after correction: