Bare Earth (DEM) mapping with LiDAR
Parcels of land with trees and vegeatation obscuring the direct view of the ground and terrain are challenging to map and do accurate land planning. Trees block terrestrial GPS antennas and hide the details of the terrain. By getting above the trees we can get excellent GPS signals and, by using laser scanning equipment we can shoot down in between the trees and get bare earth measurements.
In the image on the right there are contour lines made from the lidar points that made it's way to the ground. Now we see clearly the low areas, slopes and knobs that were hidden by trees in the first image.
In the image on the left you can see the trees and we can tell there is a depression cutting through the image on a diagonal but, to no great detail.