Hello
Are there absolute measurement devices? Device that can measure absolute height of a point?
for example lets say I need to measure two point when each point is on different location, but what I need to know is the differential between the two points although I have different ground height for each point, and the ground height is unknown (in comparison to sea level height)
p.s. (for moderator)
I asked the same Q in a different format before, hope it's not a problem, if so, let me know