okansas.blogspot.com Occassional thoughts about orienteering
Saturday, October 10, 2009
Some Lidar data from one of my current mapping projects
I discovered another program for using Lidar data. Microdem has a feature that I've made use of. I can take a "DEM" file and create an image that lets me see quite a lot of the detail.
Below is an area that I've started mapping. What is especially useful is that I can pick out the bottom of small ditches and streams. The bottom of the image - what looks like a fuzzy television picture - is some sort of error. I haven't figured out what is going on. The DEM data covers that part of the terrain, but for some reason I can't get Microdem to show it.
Below are contours (2 meter) generated from the Lidar bare earth data. I added the trails by running the area with a GPS and then using the track to draw the trails. It isn't perfect, but it is a good start.
I also use the Lidar "intensity" data to pick out some detail. For the most part I use the intensity data to pick up vegetation - individual trees and vegetation boundaries. Sometimes I'm able to pick out subtle vegetation information. I think there is the potential to get a lot more information out of the intensity image than I've managed to get.
