All Questions
Tagged with reprojection-mathematics or coordinate-system
8,699 questions
0 votes
0 answers
16 views
Reproject MODIS LAI (VJ115A2H) to geographic (EPSG=4326)
I am trying to reproject MODIS LAI data (you can download some sample here). I followed the instruction here to use rioxarray to do the job, but the result does not match the map (I used OpenStreetMap ...
- 77
0 votes
1 answer
64 views
Why does QGIS not recognize FlatGeobuf CRS?
I've been having issues viewing FlatGeobuf (FGB) files in QGIS. When I drag and drop any FGB into the Layers panel, I get this warning: That file I used (UScounties.fgb) is official test data from ...
- 1,367
0 votes
0 answers
17 views
Assessing the success of GEOID conversion using VDatum
I have a set of LAZ files that I'm trying to convert to GEOID18. The original files are assigned EPSG:6350+5703 - GEOID12B. I reprojected the files to EPSG:6340+5703 - GEOID12B using PDAL and then ...
4 votes
1 answer
151 views
How to transform a GeoJSON in EPSG:4326 to EPSG:27700 using OSTN15, and verify the result in QGIS?
I have the EPSG:4326 coordinates of a point stored in src.geojson: { "type": "FeatureCollection", "name": "main", "features": [ { "type": &...
- 3,380
1 vote
0 answers
26 views
OpenLayers and South Africa Coordinate System
I'm trying to wrap my head around this datum. I found this article : South Africa Projections I currently have OpenLayers loading WKT string to set the projection when in an area then overlaying a ...
- 121
2 votes
1 answer
59 views
Getting rid off black/RGB pixels on edges caused by during reprojection with Python
I have large .tif file, and would like to reproject it and then create COG. But as a final result I have interrupted pixels on edges. How can i remove them? Furthermore, the values are not only 0, ...
- 85
3 votes
2 answers
155 views
Using rounded/unique projections in QGIS
I'm working on creating visually interesting maps for practice. I'm currently attempting to map a world map in a Cassini, Gauss-Kruger, or sinusoidal projection, but I'm having a hard time convincing ...
- 31
0 votes
0 answers
36 views
Add custom CRS in QGIS resources DB
I have a custom CRS that I want to use regardless of the profile I am currently working in. I can add the CRS to resources/srs.db and to resources/qgis.db (and to profile/qgis.db). A CRS added to ...
- 309
4 votes
1 answer
515 views
Why did the British set both +x_0, +y_0 and +lat_0, +lon_0 to nonzero values in EPSG:27700?
I would like to understand better the historical reasoning behind some coordinate system definitions. I am working with EPSG:27700. The proj4 string of this CRS, according to gdalsrsinfo EPSG:27700 -o ...
- 3,380
5 votes
1 answer
156 views
Which transformation option I chose after I was offered to make a choice in QGIS?
I have an src.gml file containing parcel data from the Isles of Scilly (gov.uk site). This is how I got src.gml: wget https://use-land-property-data.service.gov.uk/datasets/inspire/download/...
- 3,380
0 votes
0 answers
35 views
CRS coordinate correction to Google Earth
I would like to know if there is a specific correction that is applied when exporting coordinates from certain reference systems to KML/KMZ for shapefiles to be located to its actual position on the ...
- 1
0 votes
1 answer
76 views
CRS of Base Maps in QGIS
I've been wondering if the CRS of base maps in QGIS (3.40.5) reprojects to the projects' CRS or the base map's CRS and the project's CRS are like two different layers where we can only work with the ...
- 1
1 vote
1 answer
71 views
OGRCoordinateTransformation.Transform() gives wrong coordinates
I'm trying to do some local to global (EPSG:3042 to EPSG:4326) transformations in a ROS2 c++ script using GDAL. OGRCoordinateTransformation *Transformation; OGRSpatialReference poLocal, poGlobal; ...
2 votes
1 answer
52 views
Modified/custom coordinate system in ArcGIS Pro for small scale map of Russia in polar projection
Our development team is currently in a conundrum of trying to accurately georeference a small scale map of Russia that is in a very specific Polar projection. Would anyone have a recommended Custom or ...
- 21
0 votes
0 answers
37 views
Can I use r.walk to measure distance in an equirectangular (Plate-Carree) projection?
In general, you can't use r.cost to measure distances on a Plate-Carree/equirectangular map because the cost of entering a square differs based on direction: 1 degree of latitude is constant, but 1 ...
- 11