Thew Associates utilizes a RIEGL miniVUX-1 LiDAR sensor mounted on an Altus Intelligence ORC2 helicopter UAV system. Mounting a LiDAR sensor on a UAV platform is a relatively new technology in the land surveyor’s toolbox. We have addressed some common questions we have received from clients when looking to deploy the technology.

  • UAV LiDAR Deliverables:

    The RIEGL miniVUX-1 LiDAR sensor that Thew Associates’ utilizes is equipped with a RGB camera which allows us to provide a high density colorized point cloud to clients. The general output of a LiDAR sensor is a .LAS file. This file contains vector data for every point within the cloud. Therefore, many different “Layers” of data can be extracted from the .LAS file. These layers can be translated to different types of GIS formats such as 3D Face, 3D Mesh, vectors, TIN’s, DSM’s, DTM’s, break lines, planimetric lines, etc.

    A sample of deliverables include:

    • Raw Point Cloud - Attributes include: XYZ, Intensity, Return #
    • Classified Point Cloud - Attributes include everything from Raw Point Cloud plus unique classification of buildings, vegetation, powerlines, utility poles, ect.
    • Extracted features - Buildings, trees, etc.
    • Rasters - Digital Elevation Models, Digital Surface Models, and Intensity rasters.
    • Contours (GIS or CAD formats)
    • AutoCAD breaklines and features
  • Can you collect LiDAR data in “leaf-on” conditions?

    Leaf on conditions are referring to the ability to measure the ground surface under a canopy of vegetation. Unlike with LiDAR data collected via manned aircraft, it is possible to penetrate the leaf canopy with UAV LiDAR due to the lower altitude and speed of the UAV flight. Generally, if you can see sun light under the canopy, in theory the UAV LiDAR should penetrate the canopy as well. The mission planning for collecting data in high vegetation requires multiple flight lines, slower speeds, higher overlap and possibly lower altitudes. These parameters are determined based on the end use of the data, site logistics and other non-static variables.

  • What applications are there for UAV LiDAR?

    • Topographic surveying and mapping
    • Powerline and energy infrastructure mapping and inspections
    • Vegetation management
    • Watershed mapping
  • What weather conditions can you fly in?

    Preferred weather conditions for UAV LiDAR missions are temperatures above 25° Fahrenheit with lights winds (15mph or less) and no precipitation.

  • How large of sites can you fly?

    Typically, we are finding that UAV LiDAR is a better alternative to manned-flight LiDAR missions on sites up to 1,000 acres in size but this is determined on a site by site basis.


Land Surveying


Hydrographic Surveying


Subsurface Utility Engineering

Laser Scanning

3D Laser Scanning Services


Drone Services


6431 US Hwy 11
Canton, NY 13617

Phone: 315-386-2776 
Fax: 315-386-1012


9478 River Road
Marcy, NY 13403

Phone: 315-733-7278
Fax: 315-797-1957

Saranac Lake

135 Broadway
Saranac Lake, NY 12983

Phone: 315-386-2776


135 Old Cove Rd, Suite 20
Liverpool, NY 13039

Phone: 315-244-2151

Thew Associates Land Surveyors
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