A group that maintains a freely available database with standard codes for coordinate systems, datums, spheroids, units and the like

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52
votes
3answers
48k views

What is the difference between WGS84 and EPSG4326?

What is the difference between WGS 84 and EPSG 4326? It seems like for a given dataset it might be both WGS 84 and EPSG 4326.
41
votes
3answers
14k views

What is the current Web Mercator projection code?

The web mercator projection, popularised by Google Maps, seems to be given a new EPSG code every couple of years. EPSG:900913 (Google in calculator text) was an unofficial code EPSG:3785 - is the ...
29
votes
2answers
25k views

What's the difference between EPSG:4326 and EPSG:900913?

I am a bit confused on EPSG:4326 and EPSG:900913. I thought that they were both same. Though as I am placing my features over GMaps, which is EPSG:4326, I need to define the srsname of the WFS layer ...
24
votes
2answers
16k views

What is the difference between EPSG:900913 and EPSG:3857?

I'm using the QGIS google layers plugin to digitize a parcel as a shapefile. Later I want to import it to PostGIS. I know that google maps use a special 'google mercator' projection. What is the ...
18
votes
3answers
4k views

Do ArcGIS SpatialReference object factory codes correspond with EPSG numbers?

I've got a project where I'm reading in geometry objects from text files to put them in ArcSDE. These geometry objects have an associated EPSG code, and I'm looking for a way to ensure they're in the ...
15
votes
3answers
10k views

How to georeference a web mercator tile correctly using gdal?

As an example I will take the following tile http://a.tile.openstreetmap.org/3/4/2.png and save it as "4_2.png". The WGS84 coordinates of this tile can be calculated or read there by clicking the ...
12
votes
2answers
2k views

Reprojecting WGS 1984 Web Mercator (EPSG:3857) in Python with GDAL

I am reprojecting rasters in python using GDAL. I need to project several tiffs from geographic WGS 84 coordinates to WGS 1984 Web Mercator (Auxiliary Sphere), in order to use them later in Openlayers ...
10
votes
2answers
2k views

How can I convert geomagnetic coordinates to geographic coordinates without doing the math myself?

I have some data which are in geomagnetic coordinates; that is, they are latitude and longitude, but in reference to the magnetic north pole in Canada rather than the geographic north pole. As you ...
9
votes
1answer
1k views

Using customized Coordinate System for Archaeological site data

I don't know so much about coordinate systems... In my office we use to deal with spatial data coming from archaeological sites. Each site has its own x-y-z coordinate system (GCS). Three simple ...
7
votes
2answers
732 views

Is there a standard vertical datum for meters below the WGS84 ellipsoid, or below MSL?

I have data I am publishing a WMS layer representing data under the surface of the water, say temperature at 100m depth. What is the accepted way to represent this in WMS GetCapabilities document? ...
7
votes
2answers
223 views

What is the difference between spatialreference.org catalogs: EPSG, ESRI, and User-defined?

I'm trying to understand EPSG codes. I've been to the spatialreference.org site, and in its "about" link, it states: "There are currently three distinct catalogs of spatial reference systems on this ...
6
votes
1answer
335 views

How to fix distortions in rendered OpenStreetMap maps?

I use OpenStreetMap in order to generate maps and add some cool stuff in it. Actually I have good results but I seem to have a problem with reporting a good image ratio when I create my generated ...
6
votes
1answer
111 views

Why isn't QGIS detecting CRS from .prj file?

I have a number of 1 km hexagonal grids that cover various counties in the United States in a postgreSQL/postGIS database. Each grid has the CRS EPSG:3857, and the counties layer has EPSG:3857. When ...
6
votes
1answer
505 views

How do I change an existing srs in QGis?

I am showing postgis data with srid 28992 (Amersfoort / RD New). But when I plot the geospatial data on a map (with openlayers plugin), the data is shown a hunderd meters off because the datum shift ...
5
votes
2answers
13k views

Change OpenLayers 3 view center

I'm using OpenLayers 3 to interact with some maps. I first declare my map: map = new ol.Map({ target: 'map', layers: [ new ol.layer.Tile({ ...
5
votes
1answer
1k views

how to add a custom SRID to Spatialite

I'd like to create a spatialite database and load it with shapefiles using the Mississippi Transverse Mercator (MSTM) projection, but it doesn't have an EPSG definition in the spatialite library of ...
4
votes
1answer
2k views

Are these two OGC WKT projections the same? And if so, why are their reference strings different?

So here is the .prj text of a federal shapefile dataset of all public airports in its native OGC WKT format: ...
4
votes
1answer
521 views

EPSG operations and operation methods

Querying through the EPSG database, I can see the tables epsg_coordoperation where transforms and conversions between different CRS are stored, and epsg_coordoperationmethod which stores the ...
4
votes
1answer
588 views

PostGIS spatial reference ID (SRID) for regular cartesian coordinate system?

I would like to store a polygon as a set of 2D points represented as x, y coordinates of a Cartesian coordinate system. Which spatial reference can I use? Looking at my spatial_ref_sys table, all the ...
4
votes
1answer
3k views

Distances in {Plate Carrée projection - EPSG:4326 - WGS84}

So, "4326 is just the EPSG identifier of WGS84" [3], indeed http://spatialreference.org/ref/epsg/4326/html/ says it is a GEOGraphic Coordinate System: GEOGCS["WGS 84", DATUM["WGS_1984", ...
4
votes
0answers
60 views

How to choose the EPSG projection?

Up until now for reprojection of my WGS84 vector (.shp) and raster files (.tif), I have been using EPSG projections based on vector/raster central point's UTM zone. But what happens if the ...
4
votes
0answers
261 views

GeoJSON shape distorted on Leaflet.js spherical mercator WMS map [closed]

I have a map with a simple WMS layer in spherical mercator projection (rendered by a OSM-Mapnik-TileCache server stack, everything is in EPSG:900913 / EPSG:3857). First: I can't understand why, if ...
3
votes
1answer
174 views

Problem with projection in layer

I'm having problems with visualizing a layer which is in EPSG:4326 Apparently the geometry looks perfect, but I don't know why, it's not in real coordinates. I have projected it to 4326 with QGIS, ...
3
votes
2answers
62 views

What is the epsg code of eurostat maps?

Shape files of Europe maps are available on the Eurostat website. I downloaded NUTS_2013_60M_SH. The tool (readOGR from the R package Rgdal) I use to load the map shows the following proj4string: ...
3
votes
2answers
709 views

Error transforming EPSG:4326 to EPSG:90013

When I'm trying to run a map on geomajas an error has occurred: o.g.internal.service.GeoServiceImpl - Problem during transformation EPSG:4326->EPSG:900913 of MULTIPOLYGON The multipolygon ...
3
votes
1answer
960 views

Definitive list of Proj4 supported coordinate systems

I need to determine the minimum set of coordinate systems supported by all tiers of my project's stack. I have a list of EPSG codes supported by Oracle and GeoServer but I'm having trouble finding a ...
3
votes
2answers
717 views

How do I convert to EPSG:3857 with GDAL?

I have some TIFs in EPSG4326 the GeoTiff info looks like: GEOGCS["WGS 84", DATUM["WGS_1984", SPHEROID["WGS 84",6378137,298.257223563, AUTHORITY["EPSG","7030"]], ...
3
votes
2answers
331 views

How do I automatically export a release of the EPSG registry?

I am trying to use the EPSG Registry API to export a release of the registry for offline use but am receiving a registry error. After following the Developer Guide I am HTTP POSTing the following XML ...
3
votes
2answers
248 views

EPSG:3575 projected bounds

I've been trying to find out what the projected bounds are for EPSG:3575 but have not been able to find a definitive answer. Normally, I'd just use the values from EPSG.io but when I tried these in ...
3
votes
1answer
519 views

Using Cassini-Soldner projection in QGIS?

I have a shapefile in a Cassini Soldner reference system centered in Monte Mario (Italian cadastre map). I want to insert these data inside QGIS in order to compare data with aerial images. When ...
3
votes
1answer
134 views

Misalignment of EPSG:4326 and EPSG:3399 coordinates

I'm having a QGIS project in local coordinates (Gauss-Kruger, EPSG:3399) with some layers in the same reference system. On top of that, I want to display point coordinates, which I digitized using ...
3
votes
1answer
266 views

Convert planar distance to ellipsoid (real) distance

I have the following linestring which approximately marks an airport runway: LINESTRING(-381578.819887 6574044.360475, -378513.534443 6574799.475787) # EPSG 3857 LINESTRING(-3.427781 50.732117, ...
3
votes
3answers
1k views

Proper gdaltransform syntax to transform a list of coordinates?

this is probably a very simple question, but I'm very new to GIS so I just need one last nudge. I've got a sense of the Linux utility gdaltransform and I am feeding it coordinate pairs in ...
3
votes
1answer
346 views

Is there no EPSG code to use for Behrmann equal-area projection in ogr2ogr?

I'm trying to use ogr2ogr to reproject some shapefiles. The projection I wish to use is Behrmann equal-area. I cannot find an EPSG code to use for the '-t_srs' part of the syntax. Is there any way ...
3
votes
1answer
26 views

Default transformation for a EPSG CRS

Is there any way to know which transformation, from available, is the default transformation for a CRS in the EPSG database? For example, EPSG:4230 has more than 30 transformation available and ...
3
votes
1answer
263 views

Local Ortho projection to Proj4

We are trying to use proj4 to project a local coordinate system to EPSG4326. We believe we have most of the string created correctly in QGIS and as follows; +proj=ortho +datum=WGS84 ...
3
votes
1answer
95 views

How to define custom projection EPSG:5714 in QGIS

I have a series of raster files with the CRS EPSG:5714. I need to define this CRS in QGIS but I'm fairly new to this and have no idea how to define the proj4 CRS for this. I searched at ...
3
votes
1answer
755 views

How to convert a geotiff from WGS84 to 3857 with gdalwarp?

I'm trying to convert images with WGS84 projection to 3857 but warp is not giving me a output I would expect. This is my command: gdalwarp -s_srs "+proj=merc +datum=WGS84" -t_srs "EPSG:3857" ...
3
votes
1answer
235 views

Why does projection WKT differ between osr.SpatialReference and gdalinfo

I am writing a simple geotiff using the GDAL python bindings, but the projection WKT reported by gdalinfo differs from the source. The script from osgeo import gdal, osr import numpy # Create ...
3
votes
2answers
197 views

How to get EPSG with OGRinfo?

Is it possible to get the EPSG code of a shapefile with ogrinfo? I know I can get layers SRS WKT with ogrinfo -so -al stands1.shp, but I am looking for the EPSG code.
3
votes
2answers
557 views

How to make QGIS recognize EPSG:31468?

I have Shapefiles without a CRS (e.g. without .prj file). I would like to set the CRS (EPSG:31468) before I pass the Shapefiles. I tried the following: Setting a .prj file manually with the string ...
3
votes
0answers
784 views

How to set GDAL/cs2cs/proj to use NTv2 grid shift file when using EPSG codes?

I am using the GDAL API for Python for a script that takes only EPSG codes for inputs to specify source and target coordinate systems. While the cs2cs command seems to handle quite well ...
3
votes
2answers
659 views

How do I convert EPSG:26986 coordinate pairs to EPSG:4326 from the MassGIS web service, the Linux command-line, or PHP?

I'm a GIS newbie, normally a PHP web applications developer. I am trying to map all boundaries of the MA state representative districts. So I just need to convert polygon coordinates from the ...
2
votes
3answers
104 views

How to find the extent of (many) EPSG CRSes?

I want to map the geographic extents / bounding boxes of a lot of EPSG CRSes. At least, those with a rectangular geographic extent. For example, take epsg:2004, visiting that page shows the extent ...
2
votes
4answers
3k views

OpenLayers transform EPSG 27700 coordinate to Google 900913

Community, I'm currelty capturing my mouse click event and trying to transform the coordinates into Long Lat. I need to get at the Long Lat as strings so I can build a url and throw it at Google ...
2
votes
2answers
84 views

What is the SRID for EPSG 102743?

I am trying to create a table in PostGIS for some LiDAR data and I need to set the the_geom column to my data's SRID. My data is in EPSG 102743, but when I try to use 102743 as my SRID as the_geom I ...
2
votes
1answer
138 views

Is it possible to visualize EPSG:102020 and EPSG:3857 at same time in QGIS?

Is it possible to visualize EPSG:102020 and EPSG:3857 at same time in QGIS? If is possible, how? Why some EPSG permit on the fly transformation and visualization and other don`t?
2
votes
2answers
456 views

Is it possible to change a Geotiffs CRS?

Hi I have created a Geotiff from the Bing Aerial photography. As it is automatically in WGS 84 it inserts perfectly into QGIS, however this image is of no use to me outside of QGIS. I need to ...
2
votes
1answer
920 views

EPSG:4326, EPSG:3857, JOSM and unprojections

It is said here that EPSG:4326 is not a projection. In my mind, a projection is a transformation of the surface of the Earth producing a flat image, notably a bitmap. We know that WGS84 (World ...
2
votes
1answer
796 views

How to convert EPSG:2163 coordinates to wgs84 in javascript

I'm currently testing a web app that calculates EPSG:2163 coordinates based on user interaction with a map created through d3.js. I wish to convert these coordinates to WGS84 in order to use various ...