Basics of Using LiDAR Data Workshop Exercises 2015

Basics of Using LiDAR Data Workshop Exercises

Exercise 1: Raster Processing ..............................................................................................................4 A. Training Data Acquisition and Description ........................................................................................... 4 B. Basic Properties - Examining Source Data ............................................................................................ 4 C. Raster Processing .................................................................................................................................. 5 Activate Spatial Analyst Extension ........................................................................................................ 5 Spatial Analyst Tools ............................................................................................................................. 5 Raster Calculator ................................................................................................................................... 6 Raster Environments............................................................................................................................. 6 Raster Processing – Depressions Example ............................................................................................ 7 Raster Clipping .................................................................................................................................... 12 Exercise 2: Minnesota LiDAR Data .................................................................................................... 13 A. Where and How to Get Minnesota LiDAR Data .................................................................................. 13 Install FileZilla...................................................................................................................................... 13 Getting Minnesota LiDAR Data – Easy as 1, 2, 3 ................................................................................. 14 Minnesota LiDAR Quick Download Guide........................................................................................... 15 B. Navigating ........................................................................................................................................... 15 RTM – Read The Manual ..................................................................................................................... 15 Site Layout .......................................................................................................................................... 16 Data Folder.......................................................................................................................................... 17 Download ............................................................................................................................................ 17 C. File Formats and Data Types ............................................................................................................... 18 Geodatabase ....................................................................................................................................... 18 Raster/DEM – GRID ............................................................................................................................. 18 Feature Data – Contours, Breaklines, Bare Earth Points and Buildings .............................................. 18 Point Cloud – LAS/LAZ......................................................................................................................... 19 Terrains ............................................................................................................................................... 19 Full Data Folder Description ............................................................................................................... 19 **NOTES – Additional Resources ............................................................................................................ 21

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“Basics of Using LiDAR Data” Workshop Exercises

Exercise 3: Visualization and Management ....................................................................................... 22 A. Display Techniques .......................................................................................................................... 222 Default Layer Properties ..................................................................................................................... 22 Stretch Types .................................................................................................................................... 233 Statistics Calculations.......................................................................................................................... 23 Adding Color ..................................................................................................................................... 244 Adding Depth and 3D Effect ............................................................................................................. 244 B. Visualization / Comparative Techniques........................................................................................... 255 Orthophoto/DEM Comparison ......................................................................................................... 255 Add MNGEO WMS Service ................................................................................................................ 255 Swipe ................................................................................................................................................. 255 C. Managing Large Datasets .................................................................................................................. 266 Basic Tips ........................................................................................................................................... 267 Strategy - Divide, Then Conquer ..................................................................................................... 2727 Batch Processing ............................................................................................................................. 2828

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“Basics of Using LiDAR Data” Workshop Exercises

Exercise 1: Raster Processing A. Training Data Acquisition and Description 1. All data will be provided and work will be done on a USB thumb-drive given to you at the beginning of the workshop exercise. This thumb-drive is to be returned to the instructor before leaving the training room. 2. Load the thumb-drive, right click on start, then left-click on “explore” 3. Double click on the “basics” folder. This is where all data will come from and be saved to. 4. Start ArcMap

B. Basic Properties - Examining Source Data 1. Start ArcMap. 2. Select “add-data” , navigate to \thumb-drive\“basics” and add DEM. 3. Select this DEM Layer, right-click  Properties. o Click the Source tab in the properties for the layer to get a full description of the layer including cell size, format, extent and spatial reference. o Now click the Symbology tab. Here you can change the color ramp. o Put a check mark on the Hillshade option to emphasize the terrain features. This does not affect the analysis or change the data, but aids in visualization – more on that later. o Once you have examined all layer properties, click OK to close the layer properties. 4. Open ArcCatalog . Navigate to the thumb-drive. 5. Observe the different notations and icons that ArcCatalog uses between, shapefiles, Arc Grids, etc. 6. Right click the Windows “Start” button, and select explore 7. Observe the how the folder and file structure is different for an Arc Grid than other formats. TIP – Always use ArcCatalog to copy, move, or delete raster data. Arc Grids utilize a two folder system with one folder containing the raster geometry, and the other “info” folder containing tabular information for ALL rasters in the same directory.

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“Basics of Using LiDAR Data” Workshop Exercises

C. Raster Processing Activate Spatial Analyst Extension 1. From the Customize Menu, select Extensions and check-on the Spatial Analyst extension.

2. Click Close Spatial Analyst Tools 1.

Launch ArcToolbox by opening the ArcToolbox Window.

2. Expand the Spatial Analyst Tools, and observe the following sub-categories: o Distance o Extraction o Hydrology o Interpolation o Map Algebra o Surface o Zonal

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“Basics of Using LiDAR Data” Workshop Exercises

Raster Calculator 1. Go to ArcToolbox > Spatial Analyst Tools > Map Algebra > Raster Calculator. 2. Observe interface and listen to demo:

Raster Environments 1. Go to ArcToolbox > Spatial Analyst Tools > Map Algebra > Raster Calculator. 2. Select Environments to access environment settings. 3. Most common raster processing environment settings to manipulate are as follows: o Processing Extent  Snap raster o Raster Analysis  Cell size  Mask o Raster Storage  Pyramid  Raster Statistics  Compression

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“Basics of Using LiDAR Data” Workshop Exercises

Raster Processing – Depressions Example For the below example, we’ll be utilizing our DEM to perform a simple depression identification. You will calculate sinks in the landscape, and then use the raster calculator to isolate those sinks. Sink Filling 1. Launch ArcToolbox by clicking the toolbar icon. 2. Click on Spatial Analyst Tools  Hydrology  Fill .

3. Input Surface Raster: DEM (select it from the drop-down). 4. Output Surface Raster: Browse to thumb-drive\basics and name 'fill_dem'. 5. Z limit: the maximum elevation difference between a sink and its pour point to be filled. o Note: The default will fill all sinks regardless of depth. 6. The output surface raster is added to your map as a new layer. 7. Spend some time zooming in to different parts of the dem, checking layers on/off to see the effect of pit-filling the DEM.

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“Basics of Using LiDAR Data” Workshop Exercises

Isolating Depressions 1. Launch the Raster Calculator by clicking on Click on Spatial Analyst Tools  Map Algebra  Raster Calculator 2. Enter formula so the result looks exactly like the formula below: “dem” – “fill_dem” 3. Output Raster – thumb-drive\basics\depressions 4. Click OK to run the calculation. 5. Observe how negative values for “depressions” indicate depth of depression.

Problem – To make use of the many other raster tools available, it’s often useful to have an integer version of the raster. Building a raster attribute table, converting the raster to a polygon, and other functions require it. Data downloaded from the LiDAR FTP server is a single-band raster, type FLOAT. However, if we convert to an integer grid as-is, we lose much of the precision (i.e. decimals) that LiDAR is so renowned for.

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“Basics of Using LiDAR Data” Workshop Exercises

Solution #1 – If your data was in meters, we could convert to feet automatically by doing the following. In this instance, we’ll convert to meters just to show you how it’s done 1. Launch the Raster Calculator by clicking on Click on Spatial Analyst Tools  Map Algebra  Raster Calculator 2. Enter formula so the result looks exactly like the formula below: "dem" / 0.3048 3. Output Raster – thumb-drive\basics\dem_ft 4. Click OK to run the calculation.

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“Basics of Using LiDAR Data” Workshop Exercises

Solution #2– We’ll convert the DEM to an integer grid, but not before multiplying by a specified amount so as to preserve the decimals. 1. Launch the Raster Calculator by clicking on Click on Spatial Analyst Tools  Map Algebra  Raster Calculator 2. Enter formula so the result looks exactly like the formula below: "dem_ft” * 1000. Multiplying by 1000 will allow us to preserve 3 decimal places. After performing whichever functions are necessary, such as conversion to polygons, we can divide by 1000 to restore to the onethousandths decimal place. 3. Output Raster – thumb-drive\basics\dem_ft1k 4. Click OK to run the calculation.

5. Launch the Raster Calculator by clicking on Click on Spatial Analyst Tools  Map Algebra  Raster Calculator 6. Enter formula so the result looks exactly like the formula below: Int("dem_ft1k"). 7. Output Raster – thumb-drive\basics\dem_int 8. Click OK to run the calculation.

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“Basics of Using LiDAR Data” Workshop Exercises

9. Alternatively, we could’ve done all of these calculations in one window by entering the following: Int(1000 * ("dem" / 0.3048))

The point of the long-hand procedure, only to reveal an “easier” way to perform the same calculation is to drive home the point of the Raster Calculator living up to the term “Map Algebra.” Any raster can be utilized with any mathematical and algebraic function to yield a wide array of results. Ultimately, this is one of the key features that makes the raster processing environment so powerful.

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“Basics of Using LiDAR Data” Workshop Exercises

Raster Clipping Clipping out portions of raster data to work on as “pilot-areas” is a critical concept used when determining best-practice workflows. In this instance, we want to work with both LiDAR data and a raster that displays conservation-value on the landscape. To make for easier processing, we need to clip this layer (EBI300) to the same extent as the DEM, and use “snap-to-raster” to ensure they have the same spatial origin. **NOTE – There are several ways to clip a raster in ArcGIS. This method, titled “extract by mask” is useful because you can utilize feature data OR raster data for a clip layer (mask). 1. Select “add-data” 2. 3. 4. 5. 6. 7.

, navigate to \thumb-drive\basics and add ebi300.

Go to ArcToolbox > Spatial Analyst Tools > Extraction > Extract by mask. Input Raster: ebi300 Mask Data: dem Output Raster: thumb-drive\basics\ebi_300_msk Select Environments Under Processing Extent, set snap raster to: DEM

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“Basics of Using LiDAR Data” Workshop Exercises

Exercise 2: Getting LiDAR Data A. Where and How to Get Minnesota LiDAR Data Minnesota LiDAR Data is at ftp://lidar.dnr.state.mn.us/ and ftp.lmic.state.mn.us/pub/data/elevation/lidar/data  

LMIC FTP download site is faster and preferred at this time Interactive DNR download and viewer to come in next few months http://arcgis.dnr.state.mn.us/gis/lidarviewer/



Large file sizes require more reliable transfer than web browser connections. Instead, use a third party FTP client. Filezilla FTP is recommended and is free. An interactive download site is currently under development – similar to International Waters Institute LiDAR Download Site at http://gis.rrbdin.org/lidarapps.htm



Install FileZilla http://filezilla-project.org/ 1. Navigate to the thumb-drive, double click “FileZilla_3.5.3_2in32-setup.exe” in the root directory of the filesystem. 2. Custom install directions will be given during the exercise to install FileZilla on the thumbdrive itself.

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“Basics of Using LiDAR Data” Workshop Exercises

Getting Minnesota LiDAR Data – Easy as 1, 2, 3 1. Open Filezilla FTP client and enter host – lidar.dnr.state.mn.us – then click “Quickconnect”. 2. Browse the remote site for LiDAR data of interest (See Quick Download Guide below). 3. Drag and drop folder geodatabase from remote site to resident file-space of your own choosing.

1

3

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“Basics of Using LiDAR Data” Workshop Exercises

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Minnesota LiDAR Quick Download Guide

MN GEO FTP LiDAR Quick Download Guide

What Geographic Scale?

What Data Type? DEM

County Contours

Where To Get It

lmic.state.mn.us/ pub/data/elevatio n/lidar/data/coun ty

FTP Download Site DEM

Smaller

Contours

lmic.state.mn.us/ pub/data/elevati on/lidar/data/co unty

Bare Earth Points

B. Navigating RTM – Read The Manual DON’T IMMEDIATELY DOWNLOAD!  

Watchmefirst.swf – Adobe Shockwave File – Video Tutorial on entire site Readmefirst.rtf – Each folder has this written description of contents of folder

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“Basics of Using LiDAR Data” Workshop Exercises

MN GEO Site Layout - /pub/data/elevation/lidar \county – this is the folder where all of the LiDAR and derived products are stored. \examples – examples of LiDAR products and data samples. \lidar_sample – contains a sample of a standardized LiDAR data packet \maps – maps and other samples depicting LiDAR or derived products, usually as PDF files. \projects – smaller geographic areas, project-specific lidar data \tile index– tile index information, graphical and .lyr file \tools – contains various tools for working with LiDAR data. \lastools – a set of open source tools for working with LAS data files. \scripts – a variety of scripts not associated with toolboxes. \toolboxes – ArcGIS toolboxes and associated files. \training – contains various training materials that have been contributed by the Authors.

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“Basics of Using LiDAR Data” Workshop Exercises

Data Folder 

Organized by tiling scheme or geographic extent AND data type o Geodatabase  All raw data packaged by USGS 1:24k Quarter-Quarter Quadrangle o Elevation_data.gdb.zip  County-wide Dataset o laz  Compressed .LAS files – RAW data only

Download Due to the size of both the county-tiled and LAS/LAZ format data, we will not be doing exercises with these data. Check the **NOTES section at the end of this exercise to view additional resources for working with these datasets. 1. Open Filezilla FTP client and enter host – lidar.dnr.state.mn.us 2. Right click in your “Filename” window and under the thumb-drive\basics folder, select “Create New Directory” 3. Name the directory “raw_data” 4. Browse the remote site pubData  Elevation  Lidar  CountyNicollet  Geodatabase  4326-24-63.gdb 5. Left click this file, hold, then drag into recently created “raw_data” directory 17

“Basics of Using LiDAR Data” Workshop Exercises

While these data download – we’ll go over some of the file formats and data types available on the LiDAR FTP server.

C. File Formats and Data Types Geodatabase o o o

Storage model that most of the LiDAR data will be delivered in elevation_data.gdb – same geodatabase name for each county – File management implications Folder – File management implications  Cannot move items within folder separately, must maintain complete hierarchy  Many contents - different data types stored within  Can store derived products within or outside-of – pros/cons to each  ESRI Proprietary Model – doesn’t transfer well to Windows world  Use ArcCatalog

Raster/DEM – GRID o o o

Most widely used – Arc GRID raster format Available in 1m, 3m, and hillshaded versions, county and quadrangle tiling schemes Used to derive several other products – Hydrology and Terrain Analysis Modules

Feature Data – Contours, Breaklines, Bare Earth Points and Buildings o o o o

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Contours are great aid in visualization of DEM, especially in areas of relatively low relief. Contour lines available as 2-foot contour interval for county and quadrangle tiling schemes. Hydro breaklines are edge-of-water polygons. Building footprints available in county and quadrangle tiling schemes (where available).

“Basics of Using LiDAR Data” Workshop Exercises

Point Cloud – LAS/LAZ o o o o

Point cloud data packaged as both LAS and LAZ files. Also provided as Bare Earth Points – easier for most ArcGIS users – requires some prep work however. LAZ files are compressed LAS files, 10 TIMES SMALLER! – Download these. CONTAIN MORE INFORMATION THAN JUST ELEVATION  Need 3rd party extension or stand-alone software to utilize.

Terrains o o o o

Combination of all above. TIN-based data model – multi-resolution. Advantage - Store elevation information at an optimized resolution. Reside in a geodatabase with the features used to construct them.

Full Data Folder Description \data – folder stores mosaiced lidar data as projects or counties. For most folks this is the data that they will want to download. \county – contains county based products that are homogenized to a standard set of products with consistent names, schemas and organization. Here you will find mosaiced DEMS (1 and 3 meter), Hydro breaklines, 2 foot contours and building outlines where available. \[county name]\elevation_data.gdb – this folder stores the elevation.gdb geodatabases (9.3 format). Each file geodatabase contains the following file structure: DEM01 - one meter DEM Available DEM03 - three meter DEM DEM03HS - Hillshade of DEM03 CONTOURS – 1 or 2 foot contours (depends on data quality) HYDRO_BREAKLINES – merged edge-of-water breaklines for entire area County BUILDINGS – Merged buildings for entire area TILE_INDEX - a tile index with a field called TILE_NAME which identifies all of the tiles. Data VALIDATION_POINTS - a feature class of the points used in the vertical accuracy assessment qaqc - a table summarizing all of the tiles and various attributes about them - used for QA/QC purposes. \projects - contains specific projects that are not organized by county. Products are not consistent from project to project. You will have to read through the provided documentation to understand the parameters of the project.

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“Basics of Using LiDAR Data” Workshop Exercises

\raw – this folder stores the raw data that was used to put together the county mosaic datasets found in \data\county. This is where you will find tiles of compressed LAS files and Geodatabase files for each of the counties. \geodatabase – this folder stores the original tiled file geodatabases (9.3 format). Each file Geodatabase contains the following file structure: CONTOUR_DATA – Feature database Available Contours – contours for tile TERRAIN_DATA – feature database Bare_Earth_Points – Bare earth points extracted from LAS files and stored as multi-point features QQ-Quad Hydro_breaklines – edge of water breakline polygons Buildings – feature class of building outlines generated from LAS files Data DEM01 – one meter DEM \LAZ – contains compressed LAS files. These compressed files are typically 10 times smaller than the original LAS files. Please download these files if you are interested in point cloud data. PLEASE NOTE: The LAS files were compressed with a utility called LASZIP.EXE. This utility is free and part of the LASTOOLS software package. This tool is available in the LAZ folder and there is also a batch file called UNZIPLAZ.BAT that will unzip all of the LAZ files in the folder. \tile_index – all tiled data are organized by 1/16th of a USGS 1:24,000 quadrangle. This folder contains the tile index that helps you identify where the tiles are and their names. This folder stores an ESRI File Geodatabase (9.3) called indx_q006kpy4 and this GDB has a feature class named indx_q006kpy4. The field that identifies the tile names is DNR_QQQ_ID.

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“Basics of Using LiDAR Data” Workshop Exercises

**NOTES – Additional Resources Not all tools are being demonstrated in these exercises for various reasons, but here are a few useful ones, should the need arise. Few are free, but often there are trial versions available. LiDAR and DEM Tools – Minnesota DNR MN DNR has developed a full toolbox of VERY useful LiDAR tools for versions 9.x and 10, available for download on the LiDAR download site here – ftp://lidar.dnr.state.mn.us/tools/toolboxes/ Toolbox highlights include the following: -Batch Convert to CAD -Calculate Surface Area -Convert Z Units from Meters to Feet -Identify Bluffs -LAS to Contours 9.3 -Points to X,Y,Z ASCII

-Wetness Index -Converting to County Coordinates -Converting Grid Z values from meters to feet -Converting to CAD Formats -Raster Split

LAS Data        

LAS Tools - ftp://lidar.dnr.state.mn.us/tools/lastools/ LP360 Lidar Tools Extension for ArcGIS - www.qcoherent.com MARS – From Merrick – stand-alone program LASTOOLS – command line resources (Free) LiDAR Handler- ArcGIS Extension by the NOAA Coastal Services Center (free) LiDAR Analyst – ArcGIS Extension - http://www.featureanalyst.com/lidar_analyst.htm LiDAR Explorer – ArcGIS Extension 3DLiDAR Viewer – Virtual Geomatics Free LAS viewer

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“Basics of Using LiDAR Data” Workshop Exercises

Exercise 3: Visualization and Management A. Display Techniques Default Layer Properties     

Stretched Display o Limits “stretch” display to 2 Standard Deviations Statistics Drive Display – based on summary stats from entire DEM Predefined color ramp – grayscale standard Nearest Neighbor Resampling Most display variables changed in Layer Properties Symbology Tab

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“Basics of Using LiDAR Data” Workshop Exercises

Stretch Types 1. Select “add-data” , navigate to root directory and add DEM. 2. Select this DEM Layer, right-click  PropertiesSymbology tab. 3. Under “stretched” view the “Histograms” button. When you adjust the histogram, you see multiple sets of vertical bars: the purple bars represent the current display values, and the gray bars represent your original values. 4. Select each of the following and zoom to examine how “stretch” type affects display, paying careful attention to the notes for each one: o Custom or Histogram Specification – Manually defined – not recommended o Standard Deviations – Standard display o Histogram Equalize – This setting accentuates minor variations – uplands in this case – by applying the value display equally across the entire histogram o Minimum/Maximum – This setting accentuates larger variations in relief - dendritic drainage in this case – by visually ignoring the tails of the histogram 5. Gamma – This can be used with Standard Deviation or Min/Max stretch types. By applying a gamma correction, you can control the overall brightness of a raster dataset, to enhance the overall contrast and interpretation of the image. Statistics Calculations 1. Select DEM Layer, right-click  PropertiesSymbology tab”stretched” sub-menu 2. Select “From Each Raster Dataset” from Statistics – then zoom to different extents

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“Basics of Using LiDAR Data” Workshop Exercises

3. If using “From Current Display Extent” for printing, you need to save as XML. 4. Select DEM Layer, right-click  PropertiesSymbology tab”stretched””Statistics” submenus to select “Import” for your previously saved XML file. Adding Color 1. Select DEM Layer, right-click  PropertiesSymbology tab”stretched” sub-menu 2. Select various displays from “color ramp” to bring out different effects. Many elevation ramps are multichromatic, a few will be demonstrated in this exercise.

Adding Depth and 3D Effect Shaded relief adds depth and perspective while simulating a lighted surface (DEM). Temporary hillshade effects can be created within Layer Properties, but are “quick and dirty,” not yielding consistent results compared to the below method. 1. ArcToolbox  Spatial Analyst Tools  Surface  Hillshade 2. Input Raster: DEM 3. Output Raster: thumb-drive\basics\hillshade

4. Arrange elevation on top of hillshade in table of contents 5. Make elevation display 35 – 50% transparent. Layer Properties Display Tab Transparency

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“Basics of Using LiDAR Data” Workshop Exercises

B. Visualization / Comparative Techniques Orthophoto/DEM Comparison

Often, the best way to understand differences in your landscape is to view each layer in conjunction with other layers. By paying careful attention to a specific portion of the landscape, one can overlay orthophotography on a DEM to gain a better understanding of the area. Add Aerial Imagery – 3 ways 1. Use ArcGIS Basemap – o Pros – Fresh data, updated regularly, can be extremely high resolution especially near urban areas o Cons – Slow, various unassociated reference layers appearing with it 2. Use downloaded imagery o Pros – Download once for your area and you have it, o Cons – Confusing website, difficult to determine which area on reference map you’re in, have to store locally 3. Add MNGEO WMS Service 1. Open ArcMap and click on 'Add Data' 2. Look in the Catalog, and click on 'GIS Servers' 3. Highlight 'Add WMS Server' so that it appears in the Name window, and hit 'Add'. An 'Add WMS Server' window will pop up. 4. To bring up the Imagery server, type http://geoint.lmic.state.mn.us/cgi-bin/wms? in the URL window. You can click on the 'Layers' button to see a list of the layers available under the wms. Click 'OK'. 5. To bring up the Scanned DRG server, type http://geoint.lmic.state.mn.us/cgi-bin/wmsz? in the URL window. You can hit the 'Get Layers' button to see a list of the layers available under the wms. Click 'OK'. 6. Now when you look under 'GIS Servers' you have two new entries: 'LMIC WMS server (aerial photography) on geoint.lmic.state.mn.us' and 'LMIC WMS server (quad sheet drgs) on geoint.lmic.state.mn.us' 7. Still in the 'Add Data' window under 'GIS Servers', highlight one of the services listed under #6 to bring it into the 'Name' window, then click on 'Add'. The service, with all of its layers, has now been added to your ArcMap project. 8. Click on the '+' to open the map service Swipe 1. To display the Effects Toolbar, right-click anywhere in the toolbar and select Effects. 2. Select the Swipe Tool to "wipe" a layer using a horizontal or vertical line across the screen.

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“Basics of Using LiDAR Data” Workshop Exercises

3. Make sure the layer you want to "swipe" is shown in the "Layer:" box. 4. Click on the map and drag to swipe (do not release mouse button; the mouse must be depressed to get the swipe effect.) Example of swipe:

C. Managing Large Datasets Basic Tips o

o o o o

Gear up – Ease of use is often hardware dependent o CPU – multiple core, fast processors o RAM – 64 bit systems allow more RAM – upgrade o Disks – High speed, large – cheap! Work locally – network speed, USB cables, etc. slow down processing Allow 20% overage for storage space – ensures better disk functionality, along with the option to defrag or disk check for bad sectors Store source elevation information only if space is available – download is fast and easy Avoid display of multiple LiDAR scenes – hang-ups

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“Basics of Using LiDAR Data” Workshop Exercises

o o o o

Image Analysis – Accelerated rendering, test this with larger display datasets Calculate BOTH Statistics AND Pyramids for faster drawing later Backup – external hard drives cheap, failing to archive data it took days to process is not Contour data can clutter screen, set appropriate scale range limiters such as 1:10,000

Strategy - Divide, Then Conquer A critical concept in working with LiDAR data involves using “pilot areas” to test processing techniques and methodology on before applying to entire dataset. The “try it and see” approach to LiDAR processing is frustrating and time consuming. Once processing steps have been tested on smaller areas, utilize batch processing or scripting to maximize “autopilot” overnight processing.

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“Basics of Using LiDAR Data” Workshop Exercises

Batch Processing o o o o

Great tactic for processing any dataset which requires running the same tool against a large number of areas With LiDAR data, the limitation is often the processing speed in which a single dataset can be run Processing in these smaller chunks is more efficient should files be missing, corrupt, or otherwise unstable Batch processing is VERY user-friendly and non-intimidating for those who don’t write code

Document version: March 2013

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“Basics of Using LiDAR Data” Workshop Exercises