Appendix; Atmospheric Correction; Hpa And Mmhg Conversion Table - Pentax W-800 Series Basic Instruction Manual

6. APPENDIX

6.1 Atmospheric correction

The speed at which light travels through the air varies depending on the temperature and
atmospheric pressure.The W-800 series is designed to measure distances at the speed of light in
order to measure accurately, atmospheric correction needs to be used. The instrument is
designed to correct for weather conditions automatically if the temperature and pressure are
input. Correction is then carried out based on the following formula.
K: Atmospheric Correction Constant
P: Atmospheric pressure (hPa)
t: Temperature(°C)
Distance after Atmospheric Correction D = Ds (1+K)
Ds: Measured distance when no Atmospheric Correction is used.

6.2 hPa and mmHg conversion table

[Converting from hPa to mmHg]
[Converting from mmHg to hPa]
42