Latest Contributions by GabrielUpchurch1

Hi John, Specifying the coordinate system under the properties of the LAS Dataset via Catalog is the correct way for the LAS Dataset.  Desktop does not contain a tool that can project LAS files directly but there are some third-party tools that can do this.  BUT, as Sephe has pointed out, you don't need to project the lidar data, instead, you need to define the correct projection.  Esri has supplementary tools that will allow you to define the projection for an LAS file but you would first need to know what it should be.  If the data was not collected in real-world coordinate space using a geographic or projected coordinate system, then I am not sure of a way you can address that. - When you add the LAS file to the LAS Dataset, what does the coordinate system under the "XY Coordinate System" tab default to? - What are the default extent values under the "General" tab?  Below is a screenshot of what I am referring to. ... View more

Hi John, Thanks for all the details and screenshots.  It definitely appears to be a spatial reference definition issue and I am seeing evidence of this in the screenshots you posted. 1. For the screenshot of the LAS Dataset, it is covering most of the earth which suggests that the units of the defined coordinate system are not the units used to actually record the coordinates of the lidar points. 2. For your DEM, the spatial reference (UTM) uses linear units of meters but its extent appears to be reported in decimal degrees.  It should also be noted that according to the extent, the DEM covers most of the earth. The GCP info appears normal with the extent values being compatible with its spatial reference. - Do you know what coordinate system the lidar data was provided in? - Did you use UTM Zone 12 for the LAS Dataset? - What is the coordinate system of the data frame for the LAS Dataset screenshot? I think the issue is that the wrong spatial reference was used for creating the DEM from the lidar data and also for creating the LAS Dataset in the screenshot above.  Another possibility is that the spatial reference reported in the header of the LAS file is not the correct spatial reference of the lidar points. ... View more

I would agree with Kishor that you need to work with the individual bands, which makes sense logically based on what you are asking the software to do.  By trying to divide a multiband raster, you are asking the software to divide each individual band by 10000, which will create 10 new datasets, and then to composite these 10 new datasets into a new multiband raster.  In the case of Divide, it is simply a mathematical operator and lacks the complex programming necessary to complete such an operation. ... View more

Yup, your assessment sounds fair to me.  I have encountered one scenario where the arcpy.sa syntax was failing for a specific tool but the arcpy.gp syntax was successful.  In that case, we used arcpy.gp in place of arcpy.sa in the script to work around the issue.  Another way to think about it is that arcpy.gp is the older approach upon which the ArcToolbox tools were built and arcpy.sa is the newer python focused approach that much of Desktop seems to be trending towards due to everyone's love of automation. My leadership recently introduced the option to contribute on GeoNet as part of my job responsibilities so I thought I would give it a shot.  The knowledge I have obtained from my current position lends itself very nicely to working the Discussions and lending assistance where I can.  In that regard, if you find any of the info I provide useful, then I would encourage you to mark it as helpful or the correct answer.  That way I can provide evidence that unleashing us on GeoNet is beneficial to ArcGIS users ... View more

Hi Gabo, This is a known issue that Esri Development is aware of and looking into.  It was submitted during the last beta testing period just prior to the final release of Pro 1.0 so it does not appear there is a public facing report of the issue. ... View more

Hi Nancy, As Jake pointed out, your data is probably in WGS84 since the units are decimal degrees (and situated in the U.K.).  We can further draw this conclusion from Owen's point that the Global Positioning System employs WGS84 for all data collection.  Owen provided the exact steps you need to follow for adding your data so I would thoroughly review his post below. In regard to the sample data you provided, it is in a projected coordinate system, unlike your data, which is in a geographic coordinate system.  Geographic coordinate systems employ an angular unit of measure (e.g., degrees of long/lat) for recording location while projected coordinate systems use linear units (e.g., meters, feet, etc.) for recording location.  Looking at the number of digits (6) in the sample coordinates, the projected coordinate system most likely has a linear unit of meters.  You might chance a guess that it is a UTM coordinate system due to this system's common usage but it could be some other local system that also employs meters or some uncommon UTM derivative.  It is possible through trial and error to figure out the correct projected coordinate system for the sample if you know where the points should be but it's always best if you can just get this information from the source. I would suggest following the instructions provided below by Owen Earley​ to properly display your points using GCS_WGS_1984 and then reproject them to GCS_OSGB_1936 using the Project tool if needed. ... View more

Glad it worked.  Your three step approach and the Visibility tool are both valid methods.  In regards to the units of the parameter, I think it is based on the linear units of the input raster.  So if your elevation raster has linear units of meters, then you would specify the outer radius you need in meters. One thing to keep in mind with the two approaches is that your three step method only considers planimetric distance from the observer point, while the outer radius setting in the Visibility tool offers both planimetric or 3D line of sight distance (depending out how you specify your radius, negative or positive value respectively).  Here is a help resource for the Visibility tool just in case you have not seen it:  Visibility—Help | ArcGIS for Desktop . ... View more

Hi John, This looks like a tough one but perhaps someone with experience processing lidar data and/or georeferencing elevation surfaces will have some useful insight.  I am not sure I will be able to provide any fruitful suggestions but I am curious about a few things. 1. What are we talking about in terms of the character and amount of misalignment between the images and the DEM? 2. Does the point cloud also exhibit the alignment issue?  You could throw the LAS file into an LAS Dataset and compare it to the imagery to determine this. 3. I have never tried this but do you have any other correctly aligned elevation surfaces you could compare the DEM to?  Or even a digital USGS topo?  Perhaps if a reference surface has high enough resolution, you could use some distinctive terrain features found in both surfaces for georeferencing purposes. ... View more

Hi Ben, I have fairly thorough knowledge of data driven pages and the help resources that are available but I need some clarification on what you are trying to accomplish. 1. What do you mean by an "index?"  Other than the index layer used to create data driven pages, I am not aware of another component (in ArcGIS terms) called an index. 2. What do you mean by "showing each of the buildings shown?"  In other words, how would you like the buildings to be shown?  Since they are already in the aerial and depicted with points, this statement is a little ambiguous. If you could provide some more details of what you are envisioning, I will be happy to pass along any of the relevant possibilities I may be familiar with. ... View more

I considered your vector-based idea as well and that is what I would have suggested had you responded that you did not have access to Spatial Analyst.  It will definitely meet your needs and is less complicated (and therefore faster as well).  My preference is towards raster analysis and modeling when it is a possible because it offers considerably more spatial analysis possibilities and allows for more creativity and flexibility than vector data.  Something to consider, I try to avoid converting between raster and vector data unless absolutely necessary due to the potential to introduce inaccuracies into your data.  If you might do further spatial analysis beyond just obtaining suitable takeoff sites then I would give some advance consideration to the possible need for any data conversions that would be necessary.  With attention to detail, the right settings and some QA/QC, you can definitely convert between raster and vector data successfully.  I just want to throw that out there because I often see users converting back and forth all willy-nilly with little thought for the processes they are undertaking. Best of luck to you! ... View more