| This is a four-part video series that has
been prepared for the University of Maine and its Surveying
Engineering Technology Program to help illustrate the
day-to-day applications of LiDAR in land surveying. They have also been prepared with the hope that they may be informational for practicing surveyors and other spatial data providers. |
| These videos have been produced in HD and
you’ll get the best picture by adjusting the YouTube
settings (little gear icon that appears in the lower right
corner of each video frame after you’ve started the video)
to HD, then pause it a second or two to buffer before going
full screen (little square icon). HD Non-Streaming Alternatives: To download; Right click over link, Save As... Part One (513 MB) Part Two (460 MB) Part Three (991 MB) Part Four (857 MB) |
| True LiDAR Stories - Part
One A Setback Study Production date: February 2014 Link: True LiDAR Stories - Part One - YouTube In Part One we look at a typical setback study utilizing the Maine Department of Environmental Protection's current criteria of Highest Annual Tide as the basis from which we measure. The building setback in this example is in a town where a more stringent setback requirement of 100' has been promulgated and is in contrast with the State of Maine's minimum building setback of 75' from salt water bodies |
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| True LiDAR Stories - Part
Two Study of A Setback Production date: February 2014 Link: True LiDAR Stories - Part Two - YouTube In Part One (True LiDAR Stories - Part One - YouTube) we looked at a typical setback study utilizing the Maine Department of Environmental Protection's current criteria of Highest *Annual* Tide as the basis from which we measure. In this part, utilizing LiDAR, we will take a closer examination of what inconsistencies are introduced by not using the Highest *Astronomic* Tide for the current National Tidal Datum Epoch and the impacts that could be seen when applied to building setbacks. In this example, applying the State of Maine's minimum building setback of 75' from salt water bodies, we see what I've referred to as Dave's Magic Shed, a fictitious 10' x 12' structure which in one year lies completely upland of the 75' setback (Highest *Annual* Tide) and in another year, completely seaward. Part Two Resources: VDatum (awesome vertical and horizontal transformation program, FREE): VDatum: NOAA/NOS/Vertical Datum Transformation Maine DEP Shoreland Zoning: Shoreland Zoning, Bur. of Land & Water Quality, Maine Department of Environmental Protection MDEP's 2013 HAT Table (currently no table for 2014): http://www.maine.gov/dep/land/slz/predictions.pdf Tidal Datums: Tidal Datums - NOAA Tides & Currents Tide Predictions: Tide Predictions - NOAA Tides & Currents XTide (awesome Unix-based program, FREE): XTide: Harmonic tide clock and tide predictor |
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| True LiDAR Stories - Part
Three That's Classified Production date: February 2014 Link: True LiDAR Stories - Part Three - YouTube In Part One (True LiDAR Stories - Part One - YouTube) and Part Two (True LiDAR Stories - Part Two - YouTube) we looked at setback issues predicated on LiDAR-derrived contours. In this part, we will take a closer examination as to which specific LiDAR points are used for contour generation and the shortcomings of the classification process that users of LiDAR data need to be aware of and when it is appropriate to employ reclassification algorithms. In this example, we see what I've referred to as a hole in the ground, an area that is clearly on open lawn yet devoid of legitimate bare ground returns and which instead have been classified as UNCLASSIFIED. Reclassification of the UNCLASSIFIED pulses allows us to fill in that hole and thereby generate contours more closely representative of the truth on the ground. Part Three Resources: USGS Center for LIDAR Information: CLICK USGS Base Specifications used in 2010-2011 deliverables: http://lidar.cr.usgs.gov/USGS-NGP%20...%28ILMF%29.pdf MCC-LIDAR is a command line application (FREE) for processing LiDAR data in forested environments. It classifies data points as ground or non-ground using the Multiscale Curvature Classification algorithm developed by Jeffrey S. Evans and Andrew T. Hudak. MCC-LIDAR's Home page: MCC-LIDAR MCC-LIDAR's How to Run MCC-LIDAR: HowToRun ? MCC-LIDAR |
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| True LiDAR Stories - Part
Four Epilog Production date: February 2014 Link: True LiDAR Stories - Part Four - YouTube In this last part, we discuss sources of LiDAR data, where you may obtain it and other geospatial products as well as taking a peek at its present coverage across the State of Maine. Lastly, is the reminder to always vet your data; both that data which is given to you as well as the data that you produce. Part Four Resources: Maine Office of GIS Home page: Maine Office of GIS Maine Office Catalog page: Maine Office of GIS USGS Center for LIDAR Information: CLICK USGS's EarthExplorer: EarthExplorer USGS Global Visualization Viewer: USGS Global Visualization Viewer |