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FEMA – Guidance for Flood Risk Analysis and Mapping – Elevation Guidance

FEMA’s elevation guidance document retires Appendix A of the Guidelines and Specifications for Flood Hazard Mapping Partners (Guidelines) and Procedure Memorandum 61 – Standards for LiDAR and Other High Quality Digital Topography, while modernizing the guidance to align with the USGS LiDAR Base Specifications v1.2, ASPRS Positional Accuracy Standards for Digital Geospatial Data (Edition 1, Version…

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Best Practices for Minimizing Errors during GNSS Data Collection

Aimed at surveyors and GIS professionals who use geodetic-quality GNSS equipment to determine positions for land planning, coastal monitoring and other purposes, this video from NOAA’s video library covers best practices for reducing errors in the areas of: 1. location and environment, 2. equipment setup and 3. observation times and accuracy checks.  

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Nominal Pulse Spacing (NPS)

In the LIDAR industry the generally accepted definition for Nominal Pulse Spacing (NPS) is the one detailed in the USGS base LIDAR Specification. That is the spacing between points in the collection when in reference to single instrument, single swath, first return only LIDAR point data. The NPS is a value that is usually predicted by…

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Point Data Record Format (PDRF)

ASPRS (American Society for Photogrammetry and Remote Sensing) LAS Specification defines the attributed that can be stored in each point data record format (0 through 10). The chart below provides a summary as to which attributes can be stored in which format. Attribute 0 1 2 3 4 5 6 7 8 9 10 X…

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LIDAR Quality Levels – Part 1

The LIDAR community has been gradually adopting the terminology “Quality Level” to categorize airborne LIDAR data. The idea is to use a simple scheme to characterize the more important features of a LIDAR data set into a few broad groups designated QLn where n is the quality level. LIDAR Quality Levels – Part 1

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New to LIDAR processing and looking for some reference material to strengthen your knowledge in the field?

May we suggest the following: Airborne Topographic Lidar Manual by Michael Renslow, Editor https://eserv.asprs.org/web/staticcontent/staticpages/4587.htm Topographic Laser Ranging & Scanning Principles & Process by Jie Shan and Charles Toth https://eserv.asprs.org/web/staticcontent/staticpages/4583.htm  Digital Elevation Model Technologies & Applications, 2nd Ed. by David F. Maune, Editor https://eserv.asprs.org/web/staticcontent/staticpages/1069.htm

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