topic Re: How to remove spikes in a raster/DEM in 3D Questions https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175523#M1117 <HTML><HEAD></HEAD><BODY><P>Strange...how did the DEM get the spike in the middle of the lake in the first place?</P><P>If the lake has a constant elevation&nbsp; (no​ assumptions here) you could assign the elevation to the DEM if you had the spatial analyst extension using the Con tool</P></BODY></HTML> Wed, 10 Jun 2015 00:12:50 GMT DanPatterson_Retired 2015-06-10T00:12:50Z How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175522#M1116 <HTML><HEAD></HEAD><BODY><P>This is an oblique view of a lake and the red circle showing a spike in the DEM.&nbsp; </P><P></P><P>How to remove the spikes?</P><P></P><P>I use a DEM and drape the image on it in ArcScene.</P><P></P><P>I have ArcGIS Desktop Advanced + 3D Analyst</P><P></P><P>Thanks!</P></BODY></HTML> Tue, 09 Jun 2015 23:07:38 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175522#M1116 WinnieLau 2015-06-09T23:07:38Z Re: How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175523#M1117 <HTML><HEAD></HEAD><BODY><P>Strange...how did the DEM get the spike in the middle of the lake in the first place?</P><P>If the lake has a constant elevation&nbsp; (no​ assumptions here) you could assign the elevation to the DEM if you had the spatial analyst extension using the Con tool</P></BODY></HTML> Wed, 10 Jun 2015 00:12:50 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175523#M1117 DanPatterson_Retired 2015-06-10T00:12:50Z Re: How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175524#M1118 <HTML><HEAD></HEAD><BODY><P>Thanks Dan.&nbsp; I don't have Spatial Analyst.&nbsp; How can I assign or fix the spike?&nbsp; </P></BODY></HTML> Wed, 10 Jun 2015 17:17:54 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175524#M1118 WinnieLau 2015-06-10T17:17:54Z Re: How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175525#M1119 <HTML><HEAD></HEAD><BODY><P>​You need the spatial analyst or its open source equivalent</P></BODY></HTML> Wed, 10 Jun 2015 18:02:02 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175525#M1119 DanPatterson_Retired 2015-06-10T18:02:02Z Re: How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175526#M1120 <HTML><HEAD></HEAD><BODY><P>Hello!</P><P></P><P>You can request free <A href="http://www.esri.com/software/arcgis/extensions/spatialanalyst">evaluation license of ArcGIS Spatial Analyst</A> if necessary. However, you can also replace the values of the elevation surface by mosaicking a constant raster with existing surface.</P><P></P><P>Here's what could be done.</P><P>- If you know constant value and the area(lake boundary for example) you can create a raster with constant elevation value by converting polygon to raster. You can use original elevation raster for cell size and snapping.</P><P><IMG __jive_id="108641" class="image-1 jive-image" src="https://community.esri.com/legacyfs/online/108641_pastedImage_1.png" style="max-width: 1200px; max-height: 900px;" /></P><P>- Once you have the constant raster created, you can mosaic the two together. Make sure you select correct parameter for pixel type, number of bands, and mosaic operator.</P><P><IMG __jive_id="108642" class="image-2 jive-image" src="https://community.esri.com/legacyfs/online/108642_pastedImage_3.png" style="max-width: 1200px; max-height: 900px;" /></P><P></P><P>Hope this helps.</P><P></P><P>Thank you,</P><P>Prasanta.</P></BODY></HTML> Wed, 10 Jun 2015 19:22:32 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175526#M1120 PrasantaBhattarai 2015-06-10T19:22:32Z Re: How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175527#M1121 <HTML><HEAD></HEAD><BODY><P>Great idea, Prasanta!</P></BODY></HTML> Wed, 10 Jun 2015 19:25:26 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175527#M1121 SepheFox 2015-06-10T19:25:26Z Re: How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175528#M1122 <HTML><HEAD></HEAD><BODY><P>Very good idea.&nbsp; It's a good alternatives when I don't have Spatial Analyst.&nbsp; I've already asked for the free trial once so I don't think they would give me another one <IMG src="https://community.esri.com/legacyfs/online/emoticons/happy.png" /></P><P></P><P>Thanks for your time Prasanta!</P></BODY></HTML> Wed, 10 Jun 2015 19:34:21 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175528#M1122 WinnieLau 2015-06-10T19:34:21Z Re: How to remove spikes in a raster/DEM https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175529#M1123 <HTML><HEAD></HEAD><BODY><P>Prasanta, I tried and it works!&nbsp; </P><P></P><P>Thanks a lot!</P></BODY></HTML> Wed, 10 Jun 2015 22:37:43 GMT https://community.esri.com/t5/3d-questions/how-to-remove-spikes-in-a-raster-dem/m-p/175529#M1123 WinnieLau 2015-06-10T22:37:43Z