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I'm using ArcMap and I want to create DEM(s) over an area to have different outputs depending on which settings/filters I put in. I have access to laser point cloud data as my input files. I've worked with the LAS dataset tools but I'm not really sure if I'm doing everything correct or not. Because the points aren't regular, maybe some interpolation method is needed first? The problem with that is, I don't have any input point features.

This link describes fairly good the steps I've made: http://www.edc.uri.edu/blog/using-las-datasets-create-functional-outputs

marked as duplicate by BradHards, PolyGeo Dec 23 '15 at 2:12

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  • Depending on what you're doing with the data, e.g. extract terrain indices like slope or performing flow accumulation and watershed mapping, you will quite likely need to interpolate the data onto a regular grid raster DEM. – WhiteboxDev Oct 21 '14 at 15:34
  • I don't think it's possible to interpolate with just using the las point files. I tried doing IDW but you couldn't use the las points as input. Maybe I need to convert them somehow before hand. – Mutumba Oct 21 '14 at 17:54
  • Yes, you can use ArcGIS to interpolate LAS files. eve_gis is right, look at LAS Dataset to Raster. If you find that it is unsatisfactory , there is always a rich set of various open-source GIS that can interpolate LAS files for you. – WhiteboxDev Oct 21 '14 at 17:58
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First, if needed, create a LAS Dataset from your .las files.

Then use LAS Dataset to Raster, select Average for a DEM output.

  • That's what I've been doing but using that last tool it's hard to see any difference between 2 rasters DEMs despite that I've tried to use for example Nearest and Average for the two but the output looks identical. – Mutumba Oct 21 '14 at 17:56
  • @Mutumba You're not likely going to see much difference between various interpolators with high-density LiDAR data. It's of such high density that even Nearest Neighbour does a reasonable job of gridding it. – WhiteboxDev Oct 21 '14 at 18:01
  • WhiteboxDev - ah thank you for clearing that out! I should have stated that I'm very new at working with LiDAR data. I may have to adjust my project then and focus on something else. – Mutumba Oct 21 '14 at 18:51
  • @evv_gis how about those processes, – Julia Jiang Mar 18 '15 at 4:29
  • @evv_gis i was wondering if those processes would be fine ? 1 import the text files into point data. 2 using "point to raster tool", select Z-value as elevation and choose 1m*1m as extent of grid to create DEM output. if not, would you plz tell me what is the difference between those two methods. – Julia Jiang Mar 18 '15 at 4:38
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Try lastools.

Many parts are free and you could BLAST2EM and get just get what you need. Do not try to interpolate lidar in ArcGIS unless you are prepared for a long wait.

You have a robust set of options and it runs from command line. It will use the TIN approach to create your dem. It is fast and efficient.

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    I tried using the tool but you could only add 1 las file and not all of them (I have 4) and I guess Las dataset to raster works fine. – Mutumba Oct 22 '14 at 13:52

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