LIDAR LIDAR (Light Detection And Ranging, also LADAR) is an optical remote sensing technology that can measure the distance to, or other properties of, targets by illuminating the target with laser light and analyzing the backscattered light.

Terrestrial Laser Scanning (TLS) Similar to LIDAR scanning, but it uses a mixture of laser scanning and photo information to make more detailed 3D models. (Really the key difference seems to be detail).

Sonar Side scan sonar Used to scan seafloor, higher quality. Full circle scanning Used by fisherman to find fish and large ships to check for debris, low quality.

123D catch (No wait hear me out) Half the time you end up with a significant amount of ground texture in your models. Instead of cutting out all of that extra data, a lot of that can be used as a good base to work off of.