Questions tagged [dem]

For questions about Digital Elevation Models (DEM), Digital Terrain Models (DTM) and Digital Surface Models (DSM)

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1answer
219 views

Error creating DEM with Nearest Neighbour tool in QGIS?

I have an issue when I am creating a DEM with the tool natural neighbour on QGIS. When I extract my data directly on Qgis I have no issue creating a DEM. My points are coming from different sources ...
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0answers
36 views

Arc Map 10.5 -Map resolution and Font Size [closed]

[![enter image description here][1]][1] [1]: https://i.stack.imgur.com/gUVPg.png*emphasized text* How do i make my features large in layout view format? My maps are blurred and very difficulty to go ...
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0answers
55 views

Labelling point elevations of raster (DEM) using QGIS

I'm trying to create a map with spot levels using an underlying 1m resolution DEM TIFF file. My thought process so far is to create a grid of points with a height value field over the area of interest ...
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1answer
39 views

How to blend DEM hillshade with QMS basemaps

I would to keep the features of the ESRI Gray (Light) basemap crisp and clear on top of a hillshaded DEM in QGIS. So far, my attempts have not been very successful. The ESRI Gray basemap shows main ...
1
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1answer
80 views

How to extract contours from .jp2 DEM dataset?

This will be a little long-winded but I'm including all information I consider relevant. Problem: I have received a data set from a municipality that is a 3-layer LiDAR JP2 DEM and need to extract ...
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0answers
29 views

Raster Calculator for DEM Resolution

I am trying to perform a raster calculation of a DEM and I would like it to have any desired resolution of my choice. How can I write the code so that I adjust the pixel height and width in feet using ...
1
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2answers
503 views

Using Ground Control Points in Agisoft Photoscan?

I'm fairly new to the Agisoft Photoscan program, but I am trying to build several models using aerial imagery and highly accurate GCPs, with coordinates collected in the field. I align my photos and ...
1
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1answer
22 views

Querying (DEFRA) height data from WSM, what's wrong with my GetFeatureInfo parameters?

I'm trying to retrieve DSM/DTM data from UK DEFRA WMS services in order to render in 3D. My background is in programming rather than GIS, although I've been dabbling a bit for a little while. I have ...
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0answers
31 views

Contour polygon created at different intervals than the desired interval

I have a DEM in WGS84 coordinates with a minimum elevation of 2083 meters and a maximum elevation of 3000 meters. I then used the Contour tool in ArcGIS 10.7 to create contour polygons at an interval ...
0
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1answer
60 views

Extracting DEM from PRISM data?

I have PRISM data which is in the following format. Are there any ways (software and methods) to extract the DEM or elevation information from these data files?
0
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1answer
133 views

EU DEM in GRS80 EVRS2000 with geoid EGG08 --> Make it comparable to Black Sea 1975 for Romania

I got contour lines for western Romania in vertical system Black Sea 1975 which is based on elevation data with 100 m resolution. Now I would like to compare that to the EU DEM with higher resolution. ...
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0answers
48 views

Optimizing identification of tree stand boundaries

I am working on a workflow to identify tree stand boundaries. My desired result is the blue lines - I know it will never be like that, but I need it to be as good as possible. My best result is the ...
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0answers
26 views

Reclassified raster to separate polygons

I have a DEM reclassified into 5 bands and I want to convert each classification into a separate polygon. Since, I have 5 classifications, hence 5 polygons will produced. Can I do this in ArcGIS?
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0answers
16 views

Identify Number of Ground Control Points in DSM Using GDAL

I am trying to use GDAL (in Python) to extract metadata from a digital surface model (.tif). I am using the "gdalinfo" command and applying different flags (e.g. -stats, -mm) to get ...
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1answer
45 views

Calculating Slope from DEM in QGIS

I have a world DEM raster in QGIS in EPSG:4326 with elevation units in meters. I'm trying to get a raster of the slope of the terrain, and I'm doing so using the "Slope" tool under "...
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0answers
10 views

Followed “InSAR TanDEM-X Bistatic DEM workflow” in ENVI but the results seems not good

I been processing the TanDEM-X for producing DEM using "InSAR TanDEM-X Bistatic DEM workflow" using ENVI scarscape but some of the results turned out to be wrong somehow meanwhile some are ...
2
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0answers
32 views

Getting characteristic high points from DEM

I use QGIS 3.14 and I have a DEM file which I'd like to use to get a point layer with most characteristic high points from that DEM. So every top of the mountain, hill, hillock, low etc should be ...
-2
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1answer
47 views

Seeking open source alternative to Spatial Analyst / 3D Analyst toolbox of ArcGIS Desktop

Is there a decent open source software alternative for the Spatial Analyst / 3D Analyst toolboxes of the ArcGIS environment? The main goal would be to demonstrate DEM interpolation and/or ...
0
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1answer
37 views

DEM for Russia in WGS84 [closed]

I'm looking for a DEM of Russia projected in WGS84. Anyone have any ideas on where to look?
3
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0answers
44 views

Using Aspect tool in QGIS

For my bachelor thesis in biology I´m working with QGIS 3.14 (Pi) and tried to create a layer where the slope aspect/expositon/exposure is presented. I´ve got a DTM1 on hands. There is this function ...
0
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2answers
39 views

Identify the coordinates of the max values resulting from using the Zonal Statistics tool

I used the Zonal Statistics tool to extract the max values of a raster/DEM layer. The attribute table shows the result, but the problem now is to identify the coordinates of the said maximum elevation....
1
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1answer
71 views

Generating DEM Generation in LPS?

I have a Cartosat 2.5 m Imagery and Block files along with DSM Data. I wanted to generate DEM using Leica Photogrammetry Suite Software. Does anyone know the steps of generating same? I have to edit ...
2
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0answers
31 views

Meaning of statement in GRASS r.horizon manual

I have a question about this statement in the r.horizon manual: "If your projection is based on distance (easting and northing), these too must be in meters. The buffer parameters must be in the ...
1
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1answer
25 views

Modelbuilder Rastercalculator ERROR 000539

As part of a larger model for iterating lake bathymetry interpolations, I'm essentially trying to establish the lake altitude as a new base level (Z=0) for the DEM surrounding the lake. (picture below ...
18
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8answers
9k views

What software to use for making digital elevation models from UAV aerial imagery?

I have a an unmanned aerial vehicle (UAV, also called a drone) and would like to use it to create a digital elevation model and orthomosaic over a smaller area (10 km2). My platform will be able to ...
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2answers
200 views

Calculating overall TRI value using QGIS

I have used the TRI (Terrain Ruggedness Index) function in QGIS>Raster>Analysis to develop TRI maps (see below). The maps are useful, but I am also trying to determine a single TRI value for the ...
2
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1answer
40 views

Get altitude value from WMS

If I load a WMS service into QGIS I could query with the selection tool for every pixel the altitude value. Where does QGIS get this altitude value from? A WMS does not normally have any altitude ...
1
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1answer
17 views

Merging two DEM rasters in ArcMap

I tried to merge two DEM-rasters without any overlapping parts using "Mosaic To New Raster" tool. However the value range of output raster doesn't look correct. Assuming that (A1,B1) and (A2,B2) are ...
0
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1answer
43 views

What global (or very large area regional) digital elevation models (DEMs) products are publicly available? [closed]

What global or large regional area DEM and/or DSM products are publicly available?
3
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2answers
78 views

Merging DEM and DSM into single raster

First things first, I am completely new to this so please bare with me if this is a bit unclear as I lack the vocabulary. I have two raster layers (a DEM and a DSM). The DEM layer covers a large ...
0
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0answers
14 views

How to sum pixels of two overlapping rasters with different extents

I have two DEM rasters which overlap and have different extents. I would like to create a new raster which sums the pixels where there is an overlap. I tried using gdal_calc first by doing A+B but ...
6
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2answers
131 views

Working with DEMs: which should I do first calculate slope or reproject?

I have some 10 m digital elevation model rasters in UTM, and I need to generate 30 m resolution slope rasters in Albers. Which should I do first: reproject the rasters, or calculate slope? In case ...
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0answers
14 views

Order of reading in Row Ordered USGS DEM (.dem) file

I am making a .dem file parser and so far https://web.archive.org/web/20180612184054/https://nationalmap.gov/standards/pdf/2DEM0198.PDF has proven very useful in providing the information needed. ...
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0answers
94 views

Transfering height information from DEM to line feature to use in profile with ArcGIS Pro?

I am using ArcGIS Pro 2.4. I want to make a height profile of a line segment. The line has no height information, so I want to transfer height information to the line from a dem. How can this be ...
-1
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1answer
17 views

10m Resolution Seamless Dataset

I'm looking for a seamless 10m (1/3 arc second) dataset on a state by state basis. Is there a resource that houses this. I am trying to run a slope and aspect analysis for a variety of states but do ...
2
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1answer
179 views

Is there a tile server for DEM data?

I'm new to GIS and I'm using QGIS 3.4.5. I've been downloading individual SRTM tiles containing DEM data and merging them together in order to see the elevation of every point in a given area (such as ...
2
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1answer
970 views

Coordinates of the lowest point in polygon

I am working in QGIS 2.6. I have a file of several polygons and I want for each one, to find the lowest point (where is it located and its elevation). I am using "Grid statistics for polygons&...
0
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0answers
42 views

Generating DSM and DEM from processed LiDAR (TIFF) on ArcGIS Pro

I have a "processed" LiDAR that is available as TIFF, I do not know how it was processed although I've read about the method of converting a LAS dataset to Mosaic, terrain, etc. I was ...
1
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1answer
84 views

Replace value in raster by another raster by ifelse (con) statement in QGIS

Previously I spent a lot of time to see answer on similar question but neither work with my problem. I have QGIS 3.4 and a DEM where I've to substitute more accurate height in cells that are ...
0
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1answer
27 views

Change rasters' z value to minus (Below sealeave)

My current raster has positive values for all features but I need them all to be negative as it is for a seafloor basin. A handful of values are negative but most are positive. I have access to ArcGIS ...
4
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1answer
186 views

Use DEM elevation attributes in vector polygon?

I am modeling glacier retreat scatching polygons on DEM surface trying to come out with 3D scatch. Is it possible to adjust "height" of polygon to follow elevation of DEM surface (eg. glacier height ...
6
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1answer
16k views

The following layers were not correctly generated. Grid

I keep getting the same error: The following layers were not correctly generated.GridYou can check the log messages to find more information about the execution of the algorithm I saw two ...
1
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0answers
21 views

Blending two overlapping DEMs using ArcMap [duplicate]

I have two point clouds with X,Y,Z which have been converted to DEM's. One is more accurate than the other. The point at which they overlap (just a 100m strip) however is very uneven. Is there a way I ...
0
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0answers
19 views

Add buildings contours to DGM for hydraulic analysis [duplicate]

I use Hydrology Terrain Analysis Tools in QGIS/ArcGis. Now I try to add some building contours to my DEM. I got building Data (Polygons) and a Raster DEM. Finally I want the buildings added to my DEM, ...
1
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1answer
84 views

Making a heightmap DEM for use in putting together a relief

I'm new to GIS, and I'm just doing this as a hobby. I've seen 3d relief maps like this one: https://i.redd.it/peq57uoa28c51.jpg and I wanted to try my hand at making my own. I used the topoView ...
0
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0answers
44 views

QGIS Slope not working properly

I'm new in QGIS and I have been having an issue with it. The thing is that I'm trying to get the slope and relief of a zone. I have the contour lines, from that I created the DEM with 'Rasterize' > ...
1
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0answers
30 views

How do I stop QGIS from crashing when trying to create a DEM from a contour line file?

I am trying to use the same methodology I have used in the past to create a DEM from a line shapefile containing contours. However, it keeps crashing when I follow this methodology. (Using QGIS 3.10.9 ...
1
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1answer
1k views

DEM reconditioning?

I'm using ArcGIS Desktop 10.5 Arc Hydro Toolbox & encountered a problem while trying to delineate watersheds respectively drainage lines. The red lines indicate my obtained drainage lines, which ...
1
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0answers
47 views

How to avoid error in “SAGA Strahler order”-process when running it on a merged terrain model file

I am trying to create a catchment in QGIS 3.8 following this tutorial: https://www.youtube.com/watch?v=2fvy9xtAHc4 However, my terrain model is originally divided into 4 overlapping tif-files. I can ...
1
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0answers
22 views

LAS to Old Format USGS 7.5 DEM

I'm trying to use an old software that only imports the old style USGS DEM info. I've found somewhere to download an entire quadrant of which I need about 1 percent. I have a current LAS file of the ...

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