Month: May 2021
Training: P4P-RTK PPK Workflow in True View EVO
A short tutorial covering the Phantom 4 Pro (P4P-RTK) Post Processing Kinematic (PPK) workflow in TrueView EVO/LP360 Drone. The workflow covers some background on the workflow, the data files you need from your P4-RTK guest sensor, PPK trajectory processing, automated and integrated Agisoft Metashape processing to create an orthomosaic and dense image matching (DIM) point…
Determine the Alternate Navigation File to Download from NASA’s CDDIS
When the auto-download of the ephemeris and alternate navigation is not working you may elect to manually determine the an alternate navigation file to download from the NASA CDDIS site while your IT resolves any connection issues. Click here to determine the ephemeris file to download from NASA’s CDDIS. Determine the start/end times in UTC…
Determine the Ephemeris File to Download from NASA’s CDDIS
When the auto-download of the ephemeris is not working you may elect to manually determine the correct ephemeris file to download from the NASA CDDIS site while your IT resolves any connection issues. Click here to determine the alternate navigation file to download from NASA’s CDDIS. Determine the start/end times in UTC or GPS for…
True View Check Point Recommendations
When using a True View 3D imaging system, what check point recommendations do you have? Check points should always be used to validate the absolute positional accuracy of imaging and 3D imaging projects. We follow the ASPRS Digital Accuracy Standards, Annex C. Its an older standard than most UAV mapping so you’ll find that it’s…
LDExport – An LP360 Command Line Executable
LP360 has several very useful command line executable utilities that can be used to simplify different tasks or improve the efficiency of large batch processes when working with substantial amounts of data or repeating processes. LDExport was added to this utility catalog with 2017.1. It simplifies the export of LAS points and surfaces, for example…
Apply a Horizontal Rotation about an Origin Point
This post applies if your grid to ground conversion requires needing to apply a horizontal rotation about an origin point and is defined by: Horizontal Translation North (tN) Horizontal Translation East (tE) Horizontal Rotation (Rz) Horizontal Origin Northing (N0) Horizontal Origin Easting (E0) Horizontal Scale Factor Then, if the horizontal scale factor is one, luckily,…
OPUS Alternatives
OPUS is an online GNSS static data post-processing service. NOAA’s Online Positioning User Service (OPUS) provides free access to high-accuracy National Spatial Reference System (NSRS) coordinates. This service is occasionally unavailable so the following links can be used to post-process your static GNSS observation. CSRS-PPP Canadian Spatial Reference System (CSRS) Precise Point Positioning (PPP) is a service…
True View Lever Arm Offset Override
Some scenarios may require you to process your True View data with different lever arm offsets or IMU mounting angles than the ones recorded in the APX-15 at the time of acquisition. For instance, if you move the system to a new drone, but forget to update the lever arm values following the applicable system…
Applying a Horizontal Scale about an Origin Point
This post applies if your grid to ground conversion requires applying a horizontal scale about an origin point and is defined by: Horizontal Origin Northing (N0) Horizontal Origin Easting (E0) Horizontal Scale Factor Scale based grid to ground transformations are probably the most common. If the origin point is not defined, it is usually implied…